Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009 15 Rainer Anton

Vol. 8 No. 1 January 1, 2012 UniversityJournal of Doubleof South Star ObservationsAlabama Page Journal of Double Star Observations

VOLUME 8 NUMBER 1 January 1, 2012

Inside this issue:

The Relative Proper Motion of G 167-29 in the Constellation Boötes 2 Joerg S. Schlimmer Astrometric Measurements of the Visual Double Star δ Boötis Chris Estrada, Aaron Gupta, Manav Kohli, Alyssa Lund, Andrew Stout, Bevin Daglen, and J. Joseph 6 Daglen

Visual Measurements of a Selected Set of 20 Double Stars 9 Kodiak Darling, Kristy Diaz, Arriz Lucas, Travis Santo, Douglas Walker Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009 15 Rainer Anton

Chico High School Students' Astrometric Observations of the Visual Double Star STF 1657 Jonelle Ahiligwo, Clara Bergamini, Kallan Berglund, Mohit Bhardwaj, Spud Chelson, 24 Amanda Costa, Ashley Epis, Azure Grant, Courtney Osteen, Skyla Reiner, Adam Rose, Emily Schmidt, Forest Sears, Maddie Sullivan-Hames, and Jolyon Johnson

A New Companion for STF 2590, WDS 19523+1021 28 Micello Giuseppe

Divinus Lux Observatory Bulletin: Report #24 32 Dave Arnold

Astrometric Measurements of Seven Double Stars, September 2011 Report 40 Joseph M. Carro Separation and Position Angle Measurements of Double Star STFA 46 AB and Triple Star STF 1843 ABC 48 Chandra Alduenda, Alex Hendrix, Navarre Hernandez-Frey, Gabriela Key, Patrick King, Rebecca Chamberlain, Thomas Frey Comparison of Data on Iota Boötes Using Different Telescope Mounts in 2009 and 2010 by the St. Mary’s School Astronomy Club Holly Bensel, Ryan Gasik, Fred Muller, Anne Oursler, Will Oursler, Emii Pahl, Eric Pahl, 54 Nolan Peard, Dashton Peccia, Jacob Robino, Ross Robino, Monika Ruppe, Peter Schwartz, David Scimeca, Trevor Thorndike

351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey 58 Rafael Caballero

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 2

The Relative Proper Motion of G 167-29 in the Constellation Boötes

Joerg S. Schlimmer

Seeheim-Jugenheim, Hessen, Germany

Email: [email protected]

Abstract: G 167-29 is a high proper motion star in the constellation Bootes. The study of the relative proper motion is pictured over an epoch of 97 years. Different sources will be used for recalculation the proper motion. The result of recalculation shows an improvement of proper motion which is given by μx = 0.100” / year for right ascension and μy = 0.337” / year for declination.

The high proper motion star G 167-29 (coordinates: 15 15 07.06 +33 18 03.3) can be found at a distance of about 300 arc seconds from δ Bootis. The star was found by the Lowell Proper Motion study in 1964 by comparison of star fields from different epochs. G 167-29 is the 29th proper motion star of plate 167, which was centered on STT192 in Co- rona Borealis. The study gives a brightness of 15.0 magnitudes and a proper motion of 0.40 arc seconds with direction of 193 degree [H.L. Giclas, R. Burn- ham, Jr., N.G. Thomas, 1964]. G 167-29 is also listed in the LSPM catalog. The LSPM study gives a brightness of 12.73 magnitudes and a proper motion of -0.046 arc seconds in R.A. and -0.356 arc seconds in declination (φ = 187.4 degree). The distance is 26.6 pc = 86.8 light years [Lepine S., Shara M., 2005]. The following figures show the proper motion of G 167-29 for the last 97 years. All figures are aligned to the angle conventions of double star observations. Figure 1 was made by F. Kaiser in 1914 on observa- Figure 1: Detail of photo from Bruce astrograph of 1914, tory Landessternwarte Heidelberg-Königstuhl with observatory Landessternwarte Heidelberg-Königstuhl, G 167 the Bruce astrograph (Figure 5). The Bruce astro- -29 is marked with lines, image was taken from HDAP, notes graph is a double telescope and has an aperture of 2 were added by the author x 0.4 m and a focal length of 2 m. To recognize plate errors in this early stage of astrophotography two

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 3

The Relative Proper Motion of G 167-29 in the Constellation Bootes

Figure 2: Detail of photo from Bruce astrograph of 1961, Figure 3: Detail of POSS2 image of 1994, Oschin Schmidt observatory Landessternwarte Heidelberg-Königstuhl, G telescope, Mount Palomar observatory, taken from The 167-29 is marked with lines, image was taken from HDAP Digitized Sky

images were recorded. Therefore two independent images can now be analyzed for each record. A third telescope with a focal length of 4 m was used for tracking control. The quality of the scanned Bruce plates is about 1 arc second per pixel. In Figure 1, G 167-29 is below the neighborhood stars. Figure 2 is also from observatory Landessternwarte Heidelberg- Königstuhl. It was made in 1961 by G. Klare. The Bruce astrograph was also used. This time all stars were in line. It is also near the time of closest approach to one of the neighborhood stars. Figure 3 was made by the POSS 2 survey in 1994 with the Oschin Schmidt telescope and G 167-29 has moved straight through the neighborhood stars. The scale of the scanned POSS2 images is also 1.0 arc second per pixel. Figure 4 was made by the author in 2011. An 8 inch Newtonian telescope with a webcam was used. The webcam was placed in the primary focus with a focal length of 800 mm. The figure shows the result of 100 stacked frames. For scale calibration the distance of both neighborhood stars was used. These stars Figure 4: Detail of webcam image, made by the author in (labeled as B and C) show no variations in distance or 2011 with 8-inch Newtonian telescope position angle over the epoch. The image scale is about 1.2 arc seconds per pixel. For plotting the relative proper motion, first the position angle of the measurements is procession cor-

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 4

The Relative Proper Motion of G 167-29 in the Constellation Bootes

Table 1: G167-29 AB (Position angle is not yet precession corrected

Source PA SEP DATE B3473a 242.99 24.392 1914.324 1914-04-29 B3474b 245.44 24.596 1914.324 1914-04-29 B9000a 284.88 17.153 1961.126 1961-02-15 B9001b 283.31 17.471 1961.126 1961-02-15 POSS2/UKS TU 319.34 20.942 1994.337 red image Author 8-inch 330.22 24.834 2011.410 Newtonian

Table 2: G167-29 AC (Position angle is not yet precession corrected

Source PA SEP DATE B3473a 131.86 34.267 1914.324 1914-04-29 Figure 5: Photo of the Bruce astrograph made by the B3474b author in 2009, left astrograph with plate B, right tele- 132.62 33.963 1914.324 scope is for tracking control, behind it is the second 1914-04-29 astrograph with plate A B9000a 104.09 30.518 1961.126 1961-02-15 B9001b rected to J2000. The maximum correction is about 104.94 31.017 1961.126 1961-02-15 0.15 degree. Then, the data are transformed from po- POSS2/UKS TU lar to Cartesian coordinates. A linear fit is calculated 84.15 32.531 1994.337 with the Gaussian method of least squares. The value red image Author 8-inch of proper motion was calculated from measurements 73.53 36.327 2011.410 of 1914 (averaged over the values from both images) Newtonian and 2011. Table 1 gives the position measurements used in Table 3: G167-29 BC (Position angle is not yet pre- this study for G 167-29 AB, Table 2 gives the position cession corrected measurements used for the AC components, Table 3 gives the position measurements for the BC compo- Source PA SEP DATE nents. In all cases the position angle is not precession B3473a 104.48 47.768 1914.324 corrected. 1914-04-29 The proper motion values of this study are given B3474b by the averaged values of AB and AC (see Figures 6 104.07 49.617 1914.324 1914-04-29 and 7). The result of recalculation of the proper mo- B9000a tion from these data sets is different to the current 104.28 47.703 1961.126 1961-02-15 values in literature (see Table 4). In comparison with B9001b the Lowell study the recalculation shows an increased 105.77 47.774 1961.126 1961-02-15 angle but a degreased value for proper motion. Com- POSS2/UKS TU pared with the LSPM values, the value for proper mo- 105.28 47.695 1994.337 tion is similar but the direction shows a difference of red image Author 8-inch calibr. about 10 degree. 103.42 (Continued on page 5) Newtonian 2011.410

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 5

The Relative Proper Motion of G 167-29 in the Constellation Bootes

Figure 6: Proper motion of G 167-29 AB. Figure 7: Proper motion of G 167-29 AC.

Polar coordinates for closest approach: Polar coordinates for closest approach: s = 17.7 as; pa= 107.2 degree s = 30.6 as; pa= 285.8 degree

Time of closest approach: T0 = 1962.3 Time of closest approach: T0 = 1956.9

Proper Motion: Proper motion: μx = -0.103 as/yr; μy = -0.332 as/yr; φ = 197.2 degree μx = -0.097 as/yr; μy = -0.341 as/yr; φ = 195.9 degree

Lepine S., Shara M.M., 2005, A catalog of northern Table 4: The relative Proper motion of G167-29 stars with annual proper motions larger than 0".15 (LSPM-NORTH catalog), Astron. J., 129, Source date μx μy μ φ 1483-1522. H.L.Giclas 1964 0.4 193 Centre de Données Astronomiques de Strasbourg, LPSM catalog 2005 -0.046 -0.356 0.359 187.4 SIMBAD Astronomical Database, http://simbad.u- This study 2011 -0.100 -0.337 0.352 196.6 strasbg.fr/simbad/ Acknowledgements The POSS2 image was taken from The Digitized Sky, Association of Universities for Research in As- This research has made use of the SIMBAD data- tronomy, http://stdatu.stsci.edu/cgi-bin/dss_form base, operated at CDS, Strasbourg, France This work made use of the HDAP which was pro- HDAP, Heidelberg Digitized Astronomical Plates, duced at Landessternwarte Heidelberg-Königstuhl http://dc.zah.uni-heidelberg.de/lswscans/res/ under grant No. 00.071.2005 of the Klaus-Tschira- positions/q/form Foundation

References H.L. Giclas, R. Burnham, Jr., N.G. Thomas, 1964, Lowell Proper Motions VI: Proper Motion Survey of the Nothern Hemisphere with the 13-inch Pho- tographic Telescope of the Lowell Observatory, Bulletin / Lowell Observatory; no. 124, v. 6 no. 5, p. 135-153.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 6

Astrometric Measurements of the Visual Double Star δ Boötis

Chris Estrada Allen Hancock College

Aaron Gupta, Manav Kohli, Alyssa Lund, Andrew Stout and Bevin Daglen Oregon Episcopal School

J. Joseph Daglen College of Idaho

Abstract: During the summer 2010 Astronomy Research Seminar at Pine Mountain Observatory, a group of students from Oregon Episcopal School met with three goals in mind: to learn essential skills necessary for astrometry, to observe and measure the double star δ Boötis and compare their results with published literature, and to use proper motion vectors to determine the type of double star. The astrometric eyepiece was calibrated using the drift method. The separation and position angle of δ Boötis was determined respectively to be 109” and 164.4˚. These where compared with data in the Washington Double Star catalog and found to be within 5% of previous measurements.

Introduction One of the double star observational teams at the summer 2010 Astronomy Research Seminar at Pine Mountain Observatory consisted of students and faculty from Oregon Episcopal School in Portland and J. Joseph Daglen, a retired physician and teacher from Caldwell, Idaho (see Figure 1). They met with their team leader, Chris Estrada, for guidance on double star observations. The students had very little experience with double stars and astronomy. Joe Daglen had previous experience with astronomy and helped the team by sharing his knowledge. This project’s three goals were: 1 . To familiarize students with methods used by astrometrists, including the process of collecting data, calibrating the eyepiece/telescope using the Figure 1: Left to Right:10-inch F6 equatorial scope, Alyssa, Bevin, Andrew, Aaron, Manav, Joseph, and (kneeling) Chris drift method, and determining the separation and position angle of a double star. 2 . To give the students the opportunity to make parison to literature data (Johnson, 2008). their first quantitative measurements and use for- 3 . To determine if the double star is an optical mulas to estimate the precision of the observations to pair or a gravitationally bound binary system by us- determine if the observations were accurate in com- ing proper motion vectors.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 7

Astrometric Measurements of the Visual Double Star δ Boötis

The double star δ Boötis was chosen based on its the standard deviation of the scale constant was 0.1 sizable separation and large disparity in luminosity arc seconds per division, and the standard error of the between the primary and secondary stars. Such dif- mean was 0.038 arc seconds per division. ferences enable the observer to clearly distinguish between the two stars (Haas, 2006). By continuously Separation collecting data from binary star separations and posi- The separation between the primary and secon- tion angles over extended periods of time, their orbits dary stars was measured by positioning and rotating and periods can be determined (Johnson & Genet, the astrometric eyepiece so that the linear scale 2007). passed through the two stars. The number of divisions between the primary and secondary stars was Calibration estimated to the nearest 0.1 of a division and re- The primary goal of the calibration process was to corded. To avoid bias, the telescope was adjusted so determine the number of arc seconds represented by that the primary star lay in a different portion of the each division on the linear scale of the astrometric linear scale for each trial. A major division on the lin- eyepiece. Alpha Cephei (Alderamin) was chosen to ear scale was placed between the primary and secon- calibrate the astrometric eyepiece because its declina- dary stars. The division was used as a “zero” point tion was between the recommended values of 60° and from which divisions were estimated left and right on 75°. The calibration star was aligned with the linear each star. The measurements from the “zero” point scale to begin the drift procedure. were then added together to yield the total number of The drift method included aligning the calibration divisions. A total of sixteen trials yielded an average star with the linear scale, turning off the motor of the of 8.15 divisions between the stars. This figure was telescope, and then recording the time it took for the then multiplied by the scale constant (13.4”/ division) star to travel from the first to the last division obtained during calibration. Thus, the average sepa- (Teague, 2004). Although the entire group was in- ration was 109”, its standard deviation was 0.44”, and volved in the drift procedure, only three students con- the standard error of the mean was 0.11”. ducted each trial. The first student observed the star through the astrometric eyepiece and signaled when Position Angle the star passed through the first and last divisions on To obtain position angle using the drift method, the linear scale. The second student recorded the time the primary star was first set in the center of the lin- (to the nearest 0.01 second) it took for the calibration ear scale of the astrometric eyepiece (Frey & Frey star to pass through the linear scale, while the third 2010). The clock drive was subsequently disabled, al- student recorded the data. However, there was only lowing the primary star to drift toward the protractor one timekeeper and one recorder for the entire cali- scale on the outer ring of the eyepiece. The angle bration process in order to reduce bias. Although the where the primary star passed through was recorded group conducted 16 trials, two were omitted due to to the nearest 0.5 degree. Although 16 trials were re- wind interference. The average drift time was 116.3 corded, one outlier was eliminated due to novice error. seconds and the standard deviation of the drift time The remaining 15 trials yielded an average of 164.4°, was found to be 1 second. a standard deviation of 0.9°, and standard error of the The group used the drift times to determine the mean of 0.25°. The data was then corrected for the number of arc seconds per division on the linear scale Celestron eyepiece, providing a final position angle (the scale constant) of the astrometric eyepiece. The measurement of 74.4° ± 0.25°. equation used to determine the scale constant was: Analysis 15.0411t cosδ According to previous literature from the Wash- Z = 60 ington Double Star (WDS) catalog, the last measured separation angle for δ Boötis in 2009 was 104.7”, and where 15.0411 is the earth’s rotational constant in arc the position angle was 78° (Mason, 2010). This study’s seconds per second, t is the average drift time, cosδ is measured separation of 109” is 4.3” (~4.5%) greater the cosine of the declination of the star, and 60 is the than those of the last recorded measurement. The number of divisions on the linear scale (Estrada et al., measured position angle of 74.4° is 3.6° (~4.6%) less 2010). We found that there were 13.4 ± 0.1 arc sec- than the last recorded measurement. According to onds per division on the linear scale of our telescope, Ronald Tanguay (1998), these differences of less than

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 8

Astrometric Measurements of the Visual Double Star δ Boötis

5% between our measurements and past measure- significance of their data. Finally, this project allowed ments suggest that our data can be considered of rea- students to communicate their original findings to the sonable accuracy. larger community both through writing a scientific The proper motion vectors cataloged in the WDS paper and presenting their results to a large group of catalog from 2009 show the primary star of δ Boötis to both students and teachers of astronomy. have a proper motion of +85 arc seconds per 1000 years in right ascension, and -111 arc seconds per 1000 years in declination. The secondary star was Acknowledgments reported to have a proper motion of +84 arc seconds We would like to thank Pine Mountain Observa- per 1000 years in right ascension and -110 arc sec- tory for allowing us to use its facilities; Russell Genet, onds per 1000 years in declination (Mason, 2010). Richard Berry, Tomas Frey, and Vera Wallen for This difference of only one milli-arc second per year in their general assistance and facilitation; and William both right ascension and declination strongly sug- Lamb for providing us with the opportunity to attend gests that the primary and secondary stars are a this workshop. gravitationally bound system moving together through space (Grocheva & Kiselev, 1998). References Estrada, C.; Johnson, J.; Weise, E.; Fisher, J.; How- Conclusions ard, T.; Salam, A.; Almich, C.; Kessinger, D.; As mentioned earlier, the goals of this project Cavanillas, S.; Matakovich, T.; Maly, K.; Wallen, were for students to gather and communicate original V.; Genet, R. 2010, Journal of Double Star Obser- data regarding the double star δ Boötis, to compare vations. 6, 230–232. their results with previously published literature on δ Boötis, and to use proper motion vectors to establish Frey, Thomas and Frey, A., 2010, Journal of Double whether δ Boötis is a true binary or an optical double. Star Observations. 6, 2–4. During this project, the students learned how to Grocheva, E and Kiselev, A., 1998, ASP Conference gather original data on the double star δ Boötis, and Series. 145, 15–18. mastered the techniques of telescope collimation and Haas, Sissy. 2006, Double Stars for Telescop. Cam- operation, calibration of an astrometric eyepiece, bridge, MA: Sky Publishing, separation and position angle measurements, and data analysis. Johnson, Jolyon M. and Genet, R., 2007, Journal of In comparison to previously published literature, Double Star Observations. 3, 147-150. the students found that the results of this study can Johnson, Jolyon. 2008, Proceedings for the 27th An- be considered reasonably accurate due to the differ- nual Conference of the Society for Astronomical ence of less than 5% between the experimental data Sciences. 25–27. and the literature. Finally, by using proper motion vectors, the students learned to determine whether or Mason, Brian. 2010, The Washington Double Star not δ Boötis may be a true binary system. Catalog. Astronomy Department, U.S. Naval Ob- During this project, the students learned many servatory. http://ad.usno.navy.mil/wds/ skills essential to astrometric research. In their effort, Tanguay, Ronald. 1998, The Double Star Observer’s the students faced many of the challenges common to Handbook. Saugus, MA: Double Star Observer. astronomers including wind interference and re- weighting the telescope to avoid backlash. They also Teague, Tom. 2004, Observing and Measuring Visual calculated the scale constant for the astrometric eye- Double Stars. ed. Bob Argyle. London: Springer. piece and conducted statistical analysis to verify the

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 9

Visual Measurements of a Selected Set of 20 Double Stars

Kodiak Darling, Kristy Diaz, Arriz Lucas, Travis Santo, Douglas Walker

Estrella Mountain Community College Avondale, Arizona

Abstract: The observations and measurements for a selected set of twenty binary stars are reported. These tasks comprised the activities in a continuation of a special mathematics course devoted to research techniques being taught at the Estrella Mountain Com- munity College in Avondale, Arizona. The fall 2010 semester focused on telescope operations, observations and measurements of a selected set of ten binary stars and an analysis of their proper motion. The spring 2011 semester extended the observational sessions and measurements to a set of an additional twenty binary stars. In addition, the comparison of a selected subset of measurements taken with a webcam was compared to visual observations. All observation were taken with a Meade 12” Schmidt Cassegrain Telescope (SCT) using the Celestron MicroGuideTM for measurements.

F/10 Schmidt-Cassegrain telescope. This system con- Introduction and Instrumentation tained the GPS feature which made initial setup and This observation program is part of a special calibration fast and easy. Visual double star meas- mathematics class conducted during the fall 2010 urements were obtained using the Celestron Mi- and spring 2011 semesters at the Estrella Mountain croGuideTM eyepiece which is a 12.5 mm F/L Ortho- Community College located in Avondale, Arizona. scopic with a reticule and variable LED. This mathematics course is designed to give students All observations were taken on the campus of an introduction to performing real-world research Estrella Mountain Community College campus lo- with the end goal of collecting measurement data cated at 330 28’ 49.46” N, 112 0 20’ 36.47” W during which is of sufficient quality to be of value to the sci- evening hours which generally consisted of between entific community. Measurement data collected dur- 6:00 and 9:00 PM local time (01:00 to 04:00 UT). Ob- ing the fall 2010 semester has been published in the servations and measurements covered the dates from April 2011 edition of Journal of Double Star Obser- late February 2011 through early April 2011. vations, Volume 7 Number 2. The approach and results for the spring 2011 semester observing sessions Selection of Stars were presented at a conference talk at the 30th An- As in fall 2010, the selection of stars for observa- nual Conference on Telescope Science in Big Bear tion and measurement were taken from the Wash- Lake, California conducted by the Society for Astro- ington Double Star Catalog (WDS). The WDS is nomical Sciences. The selection of researching binary maintained by the United States Naval Observatory stars was chosen since the observation and measure- and is the world's principal database of astrometric ments of double star systems are an area which can double and multiple star information containing po- be achieved with the use of small telescopes. sitions (J2000), discoverer designations, epochs, posi- The instrumentation used for observations and tion angles, separations, magnitudes, spectral types, measurements consisted of a Meade 12” LX200GPS proper motions and when available, Durchmus-

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 10

Visual Measurements of a Selected Set of 20 Double Stars

terung numbers and notes for the components of along the microguide’s linear axis and the telescope 108,581 star systems. The current version of the WDS drive was temporary switched off to allow the star to is updated nightly. drift down the linear scale. After an observer’s timing The initial approach in fall 2010 was to select a measurement was acquired, the telescope’s drive was set of target stars from the neglected list on the WDS reactivated and the star repositioned to begin another main web page. However, in the process of attempting timing run. A different observer took the next timing actual measurement data it was determined that measurement. This round-robin approach was applied many of the stars on the original target list of ne- to achieve a series of independent measurements for glected stars were beyond the observational capabili- each observer. These measurements were then aver- ties of the observing site and the equipment. As re- aged to produce the calibration for this observing sys- sults of these limitations, the original list was ex- tem. panded to include a broader range of stars taken from Calibration results for fall 2010 resulted in a the 18-24 hour section of the WDS catalog website. mean measurement of 38.26 seconds per drift. A his- The criteria for observations were modified to the fol- togram distribution of drift measurement points is lowing: shown in Figure 1. • Primary and companion being magnitude 9 or The process was repeated for spring 2011 which brighter resulted in the histogram shown in Figure 2 with a • At least one magnitude difference between mean drift time of 32.21 seconds. A review of Figures 1 and 2 indicates a non Gaus- the primary and companion sian distribution of observation measurements were • Separation distance being greater than 5 and obtained in fall 2010 and a more symmetric Gaussian less than about 300 arcsecs This relaxed criteria list proved to be a nice com- 9 bination of target stars in need of observation and 8 available enough for the telescope equipment. This 7 approach was duplicated for the spring 2011 semester 6 with the list of target stars now occupying the sky 5 from 5 to 9 hrs RA. 4

Frequency 3

Visual Measurements of Selected Bi- 2

nary Stars 1 Duplicating the approach in fall 2010, the meas- 0 urements of the separation distance and position an- 37 3 7.2 3 7.4 37.6 37.8 38 38.2 38.4 38.6 38 .8 3 9 39.2 Seconds per Drift gle of the selected target stars was accomplished using a standard visual observational approach. All Figure 1: Histogram of Calibration Measurements – Fall 2010 measurements were acquired utilizing the Celestron MicroGuideTM. In order to produce high quality meas-

urements, care was taken in calibrating the measure- 12 ment instrument and performing a series of test measurements for validation of results before pro- 10

ceeding to the measurements of the target stars. 8

MicroGuide Calibration 6

Care was taken during fall 2010 to calibrate the Frequency 4 Celestron MicroGuideTM in order to obtain the highest precision measurements. The technique for calibra- 2 tion was the standard star drift method with the proc- 0

1 .2 8 2 .4 6 .8 .2 4 ess being carried out over several nights using all ob- 3 1. 4 1. 3 2. 2 2. 33 3. 31 3 31.6 3 3 32 3 32 33 3 servers in order to minimize any observer and instru- Seconds per Drift mentation bias. The approach consisted of locating a target star of sufficient visual magnitude as close to Figure 2: Histogram of Calibration Measurements – the zenith as possible. An observer centered the star Spring 2011

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Visual Measurements of a Selected Set of 20 Double Stars

used in fall 2010. Separation was measured by orient- TM Table 1: Summary Results for MicroGuide Calibration ing the selected systems along the Microguide’s linear Period Average 1 STD scale, and noting their separation as indicated by the Fall 2010 38.26 0.38 scale’s tick marks. Position angle was then measured by aligning the binary systems along the linear scale, Spring 2011 32.21 0.43 with the primary star directly on mark 30, and the type distribution obtained in spring 2011. The mean secondary along the scale between marks 30 and 60. and the one standard deviation for both calibration After the stars were aligned, the telescope’s tracking runs are shown in Table 1. system was temporarily disabled, allowing the binary Using the standard calibration formula for the system to drift out of the eyepiece’s field of view. The MicroGuide resulted in a value of 7.26 arcsecs per binary system crossed over the circular scale which MicroGuide grid interval for the fall 2010 measure- runs along the edge of the telescope’s FOV, as this ments and 7.39 arcsecs per grid interval for spring happened the position of the secondary star along this 2011. The difference was attributed to equipment circular scale was noted. 90 degrees were then added calibrations during the time intervals. or subtracted from this measurement, depending upon orientation, to achieve our final Position Angle Measurements Process measurements. These processes were repeated sev- A round robin technique used for taking new eral times per system for separation accuracy. Sum- measurement data was utilized repeating the process mary of measurement data are shown in Table 2.

Table 2: Summary Data for Measures 2011

Magnitudes Last Current WDS ID Discover. Primary Sec Epoch PA SEP Epoch PA SEP 08525+2816 HJ 460AC 6.47 6.04 2005 21 273.5 2011.2 20 276.8 06212+2108 S 513AD 7.31 7.61 2009 24 264.7 2011.2 24 274.7 07183-3644 JC 10AB 4.66 5.07 1999 98 240.1 2011.2 102 241.6 08142+1741 STU 22AB-D 6.51 8.94 2002 325 230.1 2011.2 320 230.5 08476+0001 STU 23AC 7.84 7.82 2004 352 217.3 2011.204 351 219.9 06047-4505 HJ 3834AC 6.02 6.39 1999 321 196.2 2011.204 323 202.9 08102+2551 ARN 2AC 6.58 8 2007 22 188.7 2011.204 21 195.5 07040-4337 DUN 38AC 5.61 8.83 1999 335 184.9 2011.204 337 185.7 07097+6045 HJL1046AB 6.76 7.95 1999 165 182.2 2011.238 164 184.8 07013+3225 ARN 66AF 6.59 8.26 2004 301 169.9 2011.238 301 172.0 08401+2000 ENG 37AB 6.47 6.58 2010 153 148.2 2011.238 151 155.3 06376+1211 S 529AC 6.91 8.09 2002 168 142.2 2011.238 168 143.0 07260+1406 STF1088AE 7.38 8.1 1984 224 137.4 2011.244 223 119.6 08085-1952 S 563AB 7.03 7.62 2002 57 134.3 2011.244 60 140.2 06255-3504 HJ 3858AB 6.4 7.61 2007 47 131.8 2011.258 48 134.4 08404-4223 DUN 72AB 6.91 7.8 1999 360 129.8 2011.258 1 130.2 07478-1601 KNT 4AB 6.54 6.6 2002 132 129.4 2011.258 131 130.8 07183-3644 JC 10BC 5.07 8.67 1999 216 117.2 2011.263 215 118.9 06541+0641 STTA 79 7.2 7.52 2004 89 115.5 2011.263 96 117.9 07254+5633 STTA 84AB 7.72 7.75 2004 324 113.6 2011.263 325 115.0

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Visual Measurements of a Selected Set of 20 Double Stars

Figure 3: Imagery for S529 AC Figure 4: Imagery for STF1088A

Video Imagery of Selected Stars Toward the end of the visual star observing program, a Phillips 900NC video web camera was used to investigate capturing imagery of a selected set of the binary stars. The primary objective of the experiment was to determine the capabilities of low cost web cameras for use in obtaining high precision measurements of double stars. A second objective was to determine whether a web camera could obtain imagery of doubles with fainter magnitudes than would be observable with visual means. During an observing session conducted over successive nights, 8 binary star pairs were captured. Several examples are described in detail. Binary S529 AC primary is magnitude 6.91 with a secondary at magnitude 8.09. See Figure 3. The last measurement in the WDS database indicated a sepa- Figure 5: Imagery for STTA84AB ration of 142.2 arc-seconds and position angle of 160 degrees. The epoch was 2002. fainter stars was not possible with direct video cap- Binary STF1088A primary is magnitude 7.38 ture. Preliminary analysis utilizing stacking tech- with a secondary at magnitude 8.1. See Figure 4. The niques was attempted but none were successful. Addi- last measurement in the WDS database indicated a tional work needs to be performed in this area. separation of 137.4 arc-seconds and position angle of 224 degrees with an epoch of 1984. Analysis of Separation using REDUC Binary STTA84AB (Figure 5) has a primary at REDUC is a software package dedicated to double magnitude 7.72 with a secondary at magnitude 7.75. stars measurements. The latest version can be The WDS database indicates a separation of 113.6 arc downloaded free on simple demand. It is perfectly -seconds and position angle of 324 degrees with an adapted to performing measurements on imagery cap- epoch of 2004. tured with simple CCD and video cameras as demon- Overall, 8 stars were successfully imaged with strated here. The main window shown in Figure 6 magnitudes ranging from 6.4 up to 8.26. Imaging of (Continued on page 14)

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Visual Measurements of a Selected Set of 20 Double Stars

Figure 6: REDUC Main Window

Table 3: Comparison of Visual and Imaged Separation in Arc-seconds

Separation (as)

% Accuracy Star WDS Observed Imaged to WDS

STTA 84AB 115 115.5 117.3 98

STF1088AE 137.4 119.6 135.2 98

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Visual Measurements of a Selected Set of 20 Double Stars

(Continued from page 12) Acknowledgments provides the ability to load AVI files, select specific We would to thank Becky Baranowski, Depart- targets and then performs accurate measurements ment Chair for Mathematics, Physics, and Astronomy once it is calibrated. for offering this course for the year 2010/2011 and to To provide test data on the utilization of REDUC, the Estrella Mountain Community College for use of star pair S 529AC was loaded and use as a calibration equipment and facilities. set. This was applied to star pairs STTA 84AB and STF1088AE with results shown in Table 3. References This limited test shows the promise of using inex- 1. Ronald Charles Tanguay, Observing Double Stars pensive video imaging equipment for stars brighter for Fun and Science than about magnitude 9. Additional image processing techniques could be applied to image fainter stars but 2. Argyle, Bob, Observing and Measuring Visual Dou- to what magnitude limit would be obtainable is cur- ble Stars, Springer-Verlag London Limited 2004 rently unknown. 3. Sky and Telescope Magazine, March 2011 Conclusion 4. The Celestron Micro Guide Eyepiece Manual These observations provide additional informa- (#94171) tion for researchers to investigate the nature of binary systems.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 15

Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009

Rainer Anton

Altenholz/Kiel, Germany

e-mail: rainer.anton"at"ki.comcity.de

Abstract: This paper is a continuation of earlier work published in JDSO in 2010. Using a 40-cm-Cassegrain telescope in Namibia and a fast CCD camera, 87 double and multiple systems were recorded and analyzed with the technique of “lucky imaging”. Measurements are compared with literature data. Some noteworthy systems are discussed in more detail.

Introduction Instrumental The nominal focal length of the 40-cm Cas- During two weeks in September 2009, I used the segrain is 6.3 m. With my b/w-CCD camera 40-cm-Cassegrain at the Internationale Amateur (DMK21AF04, pixel size 5.6 µm square, The Imaging Sternwarte (IAS) in Namibia for observing double Source), an image scale of 0.187”/pixel was deter- stars in the southern sky [1]. Some measurements mined from measurements of reference systems, as have already been published earlier in this Journal described earlier. When using a 2x-Barlow lens, the [2]. Results for 87 more systems obtained during this scale was 0.0970“/pix. Almost always, a red filter was period are presented here. used to reduce seeing effects, as well as the chro- The technique of “lucky imaging” for recording matic aberration of the Barlow lens. Exposure times and measuring double stars is well known, and de- were from 0.5 µsec up to 0.1 sec, depending on the tails have been described in earlier papers [2,3]. star brightness and the seeing. From recordings of With “lucky imaging”, seeing effects can be drasti- some thousands of frames, I usually select the best cally reduced, and the resolution can be pushed to ones by visual inspection with the program Virtu- the theoretical limit of the telescope. The accuracy of alDub. The typical yield is about 50 to 150 frames, position measurements can even be one order of which are re-sampled and aligned with the program magnitude better than this. With a 40-cm telescope, Registax, often with the option “manual”, and finally standard deviations of separation measurements of automatically stacked. close pairs of the order of ±0.05” were obtained. Most of the 87 investigated systems are well Calibration and Measurements known, with brightness down to the range of ninth As described in earlier papers, the image scale is magnitude, with only a few dimmer ones. Thirty are determined by measuring a number of doubles with binaries with more or less well documented orbits. well known separations. All systems are suitable, for However, in many cases literature data are scarce, which literature data can unambiguously be extrapo- such that estimates of residuals are somewhat am- lated to the actual date. Main sources are the WDS biguous. For some systems, deviations from pre- [4], and the 4th Catalog of Interferometric Measure- dicted movements could be manifested. Systems, for ments of Binary Stars [5]. Results for binaries are which sufficient and trustworthy literature data ex- also compared with data from the Sixth Catalog of ist, are used for calibration of the image scale. Orbits of Visual Binary Stars [6]. 22 systems were

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Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009

found suitable as reference. In the table below, these erature data of separations appear sufficiently accu- are marked with shaded lines. The scale factors cited rate, such that they can be taken for reference. The above were essentially the same as obtained in earlier standard deviation of the resulting residuals of about work with the 40-cm telescope, with standard devia- ±0.05”, calculated versus the thus determined calibration of about ±0.05”. While the accuracy of separation tion constant, contains both contributions from errors measurements is constant, the contribution of the of own measurements, as well as of literature data, as scale factor lets the total error margin increase for is the case for the residuals of all other pairs. As was greater separations to up to ±1.0%. The position angle already mentioned above, the total, absolute error was deduced from recordings of star trails with the margin increases with separation, due to the contri- telescope drive switched off, so as to reveal the actual bution of the calibration factor with constant relative east-west-direction in the field of view. The error mar- error of ±1.0 %. Some pairs were found noteworthy, be gin depends on the separation, and ranges from ±0.1o it because of large residuals, which are marked in for wide pairs up to almost ±4o for close ones near the Figure 2, or for other reasons. resolution limit. All measurements are listed in Table 1, and the scatter of the residuals is illustrated in Fig- - The pair ε Sculptoris (HJ3461 AB, #12) seems to ures 1 and 2 (see below). be physical. A “premature” orbit has been published in 1974, but positions strongly deviate, in accordance Comments with the trend of literature data. Most of the 87 systems presented here are fairly - The multiple θ1 Orionis, the trapezium (STF bright and easily accessible with not too small tele- 748, #30), although prominent, has not often been scopes, which also means suitable for “lucky imaging”. measured. Literature data of separations, both visual Nevertheless, many of them can be deemed as and speckle, exhibit large scatter and residuals are “neglected”, as there are only few data in the litera- somewhat ambiguous. In contrast, residuals for P.A. ture. More attention is generally paid to binaries with are all within the error limits. not too long periods, for obvious reasons. Twenty-two (Continued on page 23) systems were found, for which extrapolations of lit-

Figure 1: Plot of the residuals of the position angle versus Figure 2: Plot of the residuals delta rho versus rho. Note separation rho. Note semi-logarithmic scaling. Full rhombs semi-logarithmic scaling. Full circles indicate pairs used for indicate 22 pairs used for calibration, open rhombs all oth- calibration, open circles all others. Three of them with re- ers. Open squares refer to the system θ1 Orionis, the siduals exceeding the error limits are marked with their note "trapezium". The increase of scatter towards small separa- numbers. Open squares refer to the system θ1 Orionis, the tions is due to the fixed image resolution. The standard de- trapezium. The standard deviation for only the calibration viation for only the calibration systems is ±0.53o. systems is ±0.047" with range between –0.08" and +0.10". The curves indicate the total, absolute error margins.

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Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009

Table 1: List of measurements. Systems used for calibration are marked with shaded lines. System names, positions and magnitudes are taken from the WDS. The two columns before the last one show the differences delta of measured position angles (P.A.) and separations (rho) minus reference data. For several pairs, no residuals are given because of insufficient reference data. N is the number of measurements at different nights, or with different camera settings or filters. Individual notes are following the table. Asterisks denote systems of which images are shown in the figures.

P.A. rho delta delta PAIR RA + DEC MAGS DATE N NOTES meas. meas. P.A. rho BU 391AB 00 09.4 -27 59 6.13 6.24 258.5 1.38 2009.712 3 -0.4 -0.01 1

BU 395 00 37.3 -24 46 6.60 6.20 95.6 0.50 2009.708 3 +3.7 +0.04 2

HDO 182 00 42.7 -38 28 6.60 7.01 20.6 0.70 2009.706 2 +0.1 -0.02 3

DUN 2 00 52.4 -69 30 6.70 7.35 81.6 20.41 2009.714 1 +0.6 +0.03 4

HJ 3416AB 01 03.3 -60 06 7.58 7.67 129.2 5.11 2009.720 2 -0.1 +0.04 5

RST1205AB 4.02 6.80 110.0 0.57 2009.722 1 -0.4 +0.03 01 08.4 -55 15 6 RMK 2AB-C 4.00 8.23 239.4 6.78 2009.722 1 -2.0 ~0

BU 1229 01 19.3 -34 29 8.51 8.74 275.6 0.76 2009.710 1 -1.1 +0.02 7

STF 113A-BC 01 19.8 -00 31 6.45 6.99 19.5 1.67 2009.726 1 ~0 +0.03 8

HJ 2036 01 20.0 -15 49 7.40 7.61 339.5 2.34 2009.726 1 ~0 +0.02 9

HJ 3447 01 36.1 -29 54 5.97 7.35 183.0 0.77 2009.709 2 -2.5 -0.04 10

DUN 5 01 39.8 -56 12 5.78 5.90 188.0 11.60 2009.714 2 -0.4 -0.05 11

HJ 3461AB 01 45.6 -25 03 5.38 8.50 20.4 5.10 2009.707 2 ~0 +0.26 12

HJ 3475 01 55.3 -60 19 7.18 7.23 77.4 2.49 2009.726 1 ~0 ~0 13

STF 186 01 55.9 +01 51 6.79 6.84 66.5 0.81 2009.706 2 -0.2 -0.05 14*

H 2 58 01 59.0 -22 55 7.28 7.56 302.5 8.77 2009.726 1 +0.5 +0.07 15

BU 738 02 23.2 -29 52 7.60 7.97 213.4 1.86 2009.708 1 +1.3 +0.04 16

HJ 3506 02 33.8 -28 14 4.95 7.71 245.0 10.80 2009.718 1 ~0 ~0 17

BU 741AB 8.06 8.20 342.9 0.88 2009.707 1 +0.7 -0.03 02 57.2 -24 58 18* S 723AC 8.06 7.68 225.6 29.34 2009.707 1 - -

HJ 3555 03 12.1 -28 59 3.98 7.19 299.7 5.24 2009.708 1 -0.2 +0.02 19

DUN 15 03 39.8 -40 22 6.93 7.72 328.6 7.78 2009.723 1 +0.5 +0.07 20

DUN 16 03 48.6 -37 37 4.72 5.25 216.2 8.39 2009.723 1 -0.2 +0.02 21

STF 470AB 03 54.3 -02 57 4.80 5.89 349.0 6.98 2009.721 4 +0.3 +0.08 22*

BU 184 04 27.9 -21 30 7.40 7.70 248.3 1.87 2009.726 1 ~0 ~0 23

HJ 3683 04 40.3 -58 57 7.33 7.45 89.7 3.66 2009.726 1 ~0 +0.04 24

STF 590 04 43.6 -08 48 6.74 6.78 318.2 9.38 2009.721 1 +0.2 +0.14 25

DUN 18AB 04 50.9 -53 28 5.61 6.24 58.5 12.80 2009.726 1 +0.5 +0.1 26

STT 98 05 07.9 +08 30 5.76 6.67 300.4 0.86 2009.710 1 ~0 -0.02 27

STT 517AB 05 13.5 +01 58 6.79 6.99 241.0 0.66 2009.710 1 ~0 +0.01 28*

STF 728 05 30.8 +05 57 4.44 5.75 44.1 1.25 2009.710 1 -0.8 -0.02 29

Table continued on next page.

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Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009

Table 1 continued: List of measurements. Systems used for calibration are marked with shaded lines. System names, positions and magnitudes are taken from the WDS. The two columns before the last one show the differences delta of measured position angles (P.A.) and separations (rho) minus reference data. For several pairs, no residuals are given because of insufficient reference data. N is the number of measurements at different nights, or with different camera settings or filters. Individual notes are following the table. Asterisks denote systems of which images are shown in the figures.

P.A. rho delta delta PAIR RA + DEC MAGS DATE N NOTES meas. meas. P.A. rho STF 748AB 6.55 7.49 31.5 9.01 2009.710 1 +0.5 +0.23 STF 748AC 6.55 5.06 132.0 12.28 2009.710 1 ~0 +0.08 STF 748AD 6.55 6.38 96.1 21.79 2009.710 1 +0.1 -0.39 STF 748AE 6.55 11.1 350.6 4.58 2009.710 1 +0.6 -0.28 05 35.3 -05 23 30 STF 748BC 7.49 5.06 163.1 17.11 2009.710 1 +0.1 +0.21 STF 748BD 7.49 6.38 120.5 19.70 2009.710 1 +0.5 +0.30 STF 748CD 5.06 6.38 61.6 13.55 2009.710 1 -0.4 +0.35 STF 748CF 5.06 11.5 119.9 4.48 2009.710 1 -1.1 -0.12 AGC 1AB 06 45.1 -16 43 -1.46 8.5 90.0 8.78 2009.721 2 -0.1 -0.19 31 I 10AB 08 44.7 -54 43 1.99 5.57 302.3 0.57 2009.716 2 ~0 +0.04 32 RHD 1AB 14 39.6 -60 50 0.14 1.24 244.2 7.02 2009.714 1 +0.3 +0.02 33 SHJ 243AB 17 15.3 -26 36 5.12 5.12 143.4 4.98 2009.718 1 +0.6 +0.03 34 BSO 13AB 17 19.1 -46 38 5.61 8.88 255.7 10.19 2009.701 2 ~0 +0.30 35 STF2262AB 18 03.1 -08 11 5.27 5.86 284.8 1.54 2009.718 1 -0.2 -0.07 36 STF2272AB 18 05.5 +02 30 4.22 6.17 132.3 5.60 2009.718 1 +0.6 -0.08 37 H 5014 18 06.8 -43 25 5.65 5.68 3.5 1.78 2009.709 3 +1.2 +0.06 38 DUN 222 18 33.4 -38 44 5.58 6.16 358.7 21.73 2009.710 2 +0.3 - 39 BSO 14AB 19 01.1 -37 04 6.33 6.58 280.2 13.05 2009.710 1 - - 40 HJ 5075 19 04.1 -63 47 7.68 7.69 112.5 1.74 2009.721 1 -0.5 -0.06 41 HJ 5084 19 06.4 -37 04 4.53 6.42 13.3 1.37 2009.708 3 ~0 +0.03 42 GLE 3 19 17.2 -66 40 6.12 6.42 343.4 0.53 2009.716 2 +0.7 +0.01 43 DUN 226 19 22.6 -44 28 3.98 7.21 76.0 28.7 2009.714 1 - - 44 SCJ 22 19 28.2 -12 09 8.12 8.69 275.0 0.93 2009.705 1 -3.0 -0.02 45 S 722 19 39.2 -16 54 7.17 7.45 235.9 10.02 2009.714 1 +0.2 +0.04 46 HJ 599AB 5.31 12.6 279.2 45.2 2009.714 1 - - 19 40.7 -16 18 47* HJ 599AC 5.42 7.65 41.6 45.6 2009.714 1 - - DUN 227 19 52.6 -54 58 5.80 6.39 147.9 23.28 2009.721 1 -0.3 +0.10 48 STF2594 19 54.6 -08 14 5.65 6.35 170.2 35.55 2009.718 1 -0.1 ~0 49 HDO 295 20 11.1 -57 31 6.76 7.68 283.5 0.46 2009.721 1 +2.9 +0.04 50 RMK 25 20 14.9 -56 59 7.97 8.02 28.1 7.23 2009.721 1 -0.9 +0.1 51 DUN 230 20 17.8 -40 11 7.42 7.72 117.7 9.69 2009.714 1 +0.7 ~0 52 SHJ 323 AB 20 28.9 -17 49 4.97 6.88 191.3 1.50 2009.705 4 +1.2 -0.11 53 SHJ 324 20 29.9 -18 35 5.91 6.68 238.2 21.89 2009.718 1 +0.2 +0.10 54

Table continued on next page.

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Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009

Table 1 conclusion: List of measurements. Systems used for calibration are marked with shaded lines. System names, positions and magnitudes are taken from the WDS. The two columns before the last one show the differences delta of measured position angles (P.A.) and separations (rho) minus reference data. For several pairs, no residuals are given because of insufficient reference data. N is the number of measurements at different nights, or with different camera settings or filters. Individual notes are following the table. Asterisks denote systems of which images are shown in the figures.

P.A. rho delta delta PAIR RA + DEC MAGS DATE N NOTES meas. meas. P.A. rho HU 200AB 20 39.3 -14 57 5.38 7.31 121.6 0.34 2009.710 1 +1.4 +0.01 55 S 763AB 20 48.4 -18 12 7.24 7.79 293.5 15.64 2009.718 1 -0.3 +0.08 56 STF2729AB 20 51.4 -05 38 6.40 7.43 23.8 0.83 2009.697 1 -2.6 +0.05 57 RMK 26 20 51.6 -62 26 6.23 6.58 80.6 2.44 2009.720 2 -0.6 -0.01 58 HJ 3003 20 53.0 -23 47 6.57 8.57 194.4 1.53 2009.710 1 -0.9 -0.03 59 H 1 47 21 12.4 -15 00 8.25 8.31 309.8 4.15 2009.718 1 +0.7 -0.03 60 HJ 5258 21 19.9 -53 27 4.50 6.93 269.5 7.32 2009.721 4 -1.3 +0.1 61* BU 252 21 20.0 -27 18 8.75 8.84 88.1 2.17 2009.708 1 ~0 +0.02 62 BU 766AB 21 24.4 -41 00 6.24 6.88 197 ? 0.18? 2009.723 1 -3.0 -0.02 63 BU 1212AB 21 39.5 -00 03 6.94 8.44 286.1 0.50 2009.697 1 -1.0 +0.01 64 HDO 296AB 21 55.2 -61 53 6.6 6.8 106.4 0.33 2009.724 2 +1.1 -0.02 65 BU 276 22 00.8 -28 27 5.70 6.77 112.6 1.86 2009.710 1 ~0 ~0 66 H N 56AB 22 14.3 -21 04 5.63 6.72 112.2 5.23 2009.720 8 +0.8 - 67 I 20 22 18.0 -62 49 7.36 8.42 187.8 0.64 2009.721 1 ~0 +0.02 68 BU 172AB 22 24.1 -04 50 6.45 6.63 38.7 0.38 2009.705 1 -1.4 ~0 69* PZ 7AC 22 31.5 -32 21 4.28 7.12 172.1 30.6 2009.713 3 - - 70 DUN 241 22 36.6 -31 40 5.93 7.55 31.6 93.9 2009.714 1 +0.2 +0.10 71 BU 773 23 06.9 -38 54 5.70 8.24 205.0 0.93 2009.710 1 -0.2 -0.02 72 JC 20AB 23 06.9 -43 31 4.45 6.60 113.9 1.50 2009.707 2 -1.0 -0.05 73 DUN 246 23 07.2 -50 41 6.29 7.05 253.9 8.99 2009.703 1 -0.4 +0.12 74 HU 295 23 22.7 -15 02 5.59 6.72 281.5 0.35 2009.704 3 -0.4 +0.02 75 STF3008 23 23.8 -08 28 7.21 7.67 149.3 6.60 2009.726 1 -0.2 +0.10 76 DUN 249 23 23.9 -53 49 6.14 7.07 211.4 26.5 2009.714 1 -0.6 +0.10 77 I 23 23 28.2 -56 26 7.58 8.91 353.6 0.68 2009.694 1 -0.4 -0.12 78 B 1900 23 33.3 -20 55 4.76 7.68 127.8 0.96 2009.726 1 - - 79 I 25 23 35.3 -57 30 8.45 8.43 25.0 0.70 2009.694 1 +3.2 -0.05 80* SEE 492 23 35.7 -27 29 6.84 9.18 17.2 0.63 2009.694 1 -2.8 +0.03 81* DUN 251 23 39.5 -46 38 6.53 7.27 277.6 3.88 2009.694 1 +0.5 ~0 82 HU 1550 23 41.5 -41 35 8.45 8.71 194.6 0.73 2009.694 1 +2.7 -0.04 83 H 2 24 23 46.0 -18 41 5.65 6.46 135.7 6.98 2009.714 1 ~0 +0.08 84 SLR 14 23 50.6 -51 42 8.28 8.59 72.8 0.87 2009.708 4 -0.7 -0.01 85* LAL 192 23 54.4 -27 03 6.79 7.41 268.9 6.44 2009.718 1 -1.1 +0.06 86 LAL 193 23 59.5 -26 31 8.05 8.30 169.5 10.63 2009.718 1 ~0 +0.03 87

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Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009

Notes: Terms “cpm” (common proper motion) and “relfix” (relatively fixed) refer to Burnham [7].

1. κ Sculptoris, PA decreasing. 2. in Cetus, binary, P=25y. 3. λ Sculptoris, PA increasing. 4. in Tucana, although only few data, extrapolation seems fairly trustworthy, PA slowly increasing, rho slowly decreasing. 5. in Tucana, although deemed relfix, rho is slowly increasing. 6. ζ Phoenicis, AB binary, P=210y, PA fast inc. Few data for AC. 7. in Sculptor, probably binary, PA and rho dec. 8. 42 Ceti, PA inc. 9. in Cetus, probably binary, PA dec, rho inc. 10. τ Sculptoris, binary, P=1876y. 11. p Eridani, binary, P=484y. 12. ε Sculptoris, binary, a “premature” orbit has been calculated in 1969, few data. While PA close to ephemeris, and decreasing, rho devi- ates markedly. 13. in Hydrus, few data, but small scatter, PA inc. 14. in Cetus, binary, P=162y, many speckle data, see Figure 3. 15. in Cetus, few data, but relatively small scatter, PA dec, rho inc. 16. in Fornax, binary, P=305y, orbit highly in- Figure 3: Some sub-arcsecond doubles. Except for I 25, the clined. physical nature of the others is well documented with orbit calculations. See also notes # 69, 81, 28, 80, 14, and 85 (in 17. ω Fornacis, relfix, cpm. rows from top to bottom). 18. in Fornax, AB binary, P=137y, orbit highly inclined, newly computed in 2010. Few data for AC, no residuals given. PA and rho inc. See 25. 55 Eridani, cpm, while deemed relfix, large also Figure 4. scatter of rho data, residuals given versus av- 19. α Fornacis, binary, P=314y, orbit highly in- erage of last entries in speckle catalog of clined, few data. 1991 and 2004, PA inc. 20. in Eridanus, few data. 26. ι Pictoris, few data with large scatter, rho inc? 21. f Eridani, few data, but small scatter, PA and 27. 14 Orionis, binary, P=199y, many speckle rho inc. data. 22. 32 Eridani, rho fairly constant, nice color con- 28. in Orion, binary, P=312y, many speckle data, trast, see Figure 6. see Fig. 3. 23. in Eridanus, PA slow dec, rho inc. 29. 32 Orionis, binary, P=586y, many speckle data. 24. in Dorado, binary, P=240y, residuals given versus recently revised ephemeris, orbit 30. θ1 Orionis, “trapezium”, relatively large differ- highly inclined. ences of mainly rho measurements compared

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Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009

with last entries in the speckle catalog from 2002 to 2008, reason unknown. 31. α Canis Majoris, “Sirius”, binary, P=50.1y, residuals vs. ephemeris. 32. δ Velorum, binary, P=142y, difficult, because dim companion on diffraction ring, residuals vs. ephemeris. 33. α Centauri, binary, P=79.9y, residuals vs. ephemeris. 34. 36 Ophiuchi, binary, “premature” orbit, P=550y. 35. in Ara, also known as L7194, binary, P=693y, few data, recent measurements tend to deviate from calculated orbit. 36. τ Ophiuchi, binary, P=280y, many speckle data, residuals given vs. trend. 37. 70 Ophiuchi, binary, P=88.3y, many speckle data with small scatter. 38. in Corona Australis, binary, P=191y, residuals vs. ephemeris. Figure 4: The triple system BU 741 AB/S 723 AC in Fornax. 39. κ Coronae Australis, relfix, few data with large The pair AB is a physical binary with period 137 y. See also scatter, residual of rho ambiguous. note 18. 40. in Corona Australis, large scatter of literature data, no residuals given. 41. in Pavo, few data. 42. γ Coronae Australis, binary, P=122y, PA dec. 43. in Pavo, binary, P=157y. 44. β Sagittarii, large scatter of literature data. 45. in Sagittarius, also know as BU 142, binary, P=162y, many speckle data with relatively small scatter. Residuals given vs. speckle data of about the same epoch. 46. in Sagittarius, few data with large scatter. 47. 54 Sagittarii, no recent literature data of AB, large scatter of data for AC, no residuals given. Dim companion of about 13th magnitude at 252.3 o/56.8” not listed in the WDS. See Figure 5. 48. in Telescopium, cpm, few data, PA dec, rho slow inc. 49. 57 Aquilae, relfix. Figure 5: The multiple HJ 599 or 54 Sagittarii. The seeing allowed for 2 sec exposure, superposition of 40 frames. The 50. in Pavo. dim companion at upper left, which is marked with black 51. in Pavo. lines, is not listed in the WDS. See also note 47. 52. in Sagittarius, PA inc, rho almost fixed. 53. rho Capricorni, binary, P=278y, orbit highly inclined, own measurements, as well as literature data seem to deviate from ephemeris,

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Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009

residuals given vs. ephemeris. 77. in Grus, few data. 54. ο Capricorni. 78. in Phoenix, PA inc, few data. 55. τ Capricorni, binary, P=200y, peculiar scatter 79. in Aquarius, few data with large scatter, no of literature (speckle) data, residuals given vs. residuals given. ephemeris. 80. in Phoenix, PA dec. 56. in Capricornus, relfix. 81. in Sculptor, binary, P=78y, difficult, because 57. 4 Aquarii, binary, P=187y, recent rho data dim companion is close to diffraction ring of seem to deviate from ephemeris, residuals main star, not resolved with speckle interfer- given vs. ephemeris. ometry in 2008, PA fast inc. 58. in Pavo, also known as L8550, cpm, PA dec. 82. θ Phoenicis, PA increasing, rho slowly de- 59. in Capricornus, PA fast, rho slowly dec. creasing? 60. in Capricornus, probably binary, ephemeris 83. in Phoenix, few data with large scatter, PA questionable, residuals vs. speckle data from and rho increasing? 2009. 84. 107 Aquarii, rho slow inc? 61. θ Indi, cpm, PA slow dec?, rho fast inc, nice 85. in Phoenix, binary, P=117y, PA fast dec, rho color contrast, see Fig.6. fast inc. 62. in Capricornus, PA and rho dec.. 63. in Microscopium, not resolved here, but elon- gated, PA and rho estimated, both are decreasing, residuals vs. trend of literature data, last entry in speckle catalog from 1999. 64. 24 Aquarii, binary, P=49y, many speckle data with small scatter. 65. in Indus, binary, P=27.5y, orbit highly inclined, few data. 66. η Piscis Austrini, relfix, PA dec. 67. 41 Aquarii, few data with large scatter, espe- Figure 6: Two colorful doubles: Left: 32 Eridanis, spectra are cially for rho, PA dec, color contrast. G8III and A2V. Description of colors in the literature range from grapefruit-orange and silvery-blue to topaz-yellow and 68. in Tucana, binary, P=983y, PA decreasing, rho sea green. Right: theta Indi. A not so frequent case of a red slowly inc, residuals estimated vs. trend. companion to a main sequence star. Spectral class of the latter is A5V, that of the companion is not listed. Colors are de- 69. 51 Aquarii, binary, P=146y, residuals vs. scribed in the literature as light-yellow and reddish-brown. speckle data from 2009. See also notes 22 and 61. 70. β Piscis Austrinus, cpm, relfix, few data with large scatter, no residuals given. 71. in Piscis Austrinus, optical, few data, rho seems to linearly increase. 86. φ Sculptoris, also known as DUN 253, relfix. 87. also known as Arg 46, few data, PA and rho 72. υ Gruis, few data, PA and rho decreasing, slowly dec. some earlier speckle data show peculiar scatter, residuals vs. trend. 73. θ Gruis, cpm, both PA and rho seem to linearly increase. 74. in Grus, PA slowly decreasing, rho inc. 75. 97 Aquarii, binary, P=63y, residuals vs. ephemeris. 76. in Aquarius, optical, residuals vs. rectilinear extrapolation.

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Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009

(Continued from page 16) References - For the binary BSO 13/L 7194 in Ara (#35), with period of about 700 years, only few data are available [1] IAS, www.ias-observatory.org in the literature. Recent measurements of the separa- [2] Anton, R., 2010, Journal of Double Star Observa- tion tend to deviate from the ephemeris from 1957. tions, vol. 6 (2), 133-140. - The binary rho Capricorni (SHJ 323 AB, #53) exhibits a highly inclined orbit. Both own measure- [3] Anton, R., 2009, Journal of Double Star Observa- ments and literature data tend to deviate from the tions, vol. 5 (1), 65-71. currently assumed ephemeris. [4] Mason, B.D. et al., The Washington Double Star - The close pair 4 Aquarii (STF 2729 AB, #57) is a Catalog (WDS), U.S. Naval Observatory, online binary with period 187 years. Separation measures access July 2011. tend to be greater than expected from the ephemeris by about 0.05”, in accordance with literature data. [5] Hartkopf, W.I. et al., Fourth Catalog of Interfer- - Residuals for the pair H I 47 in Capricornus ometric Measurements of Binary Stars, U.S. Naval (#60) are within the error limits, when referred to re- Observatory, online access July 2011. cent speckle data, but strongly deviate from the [6] Hartkopf, W.I. et al., Sixth Catalog of Orbits of ephemeris published in 1974. With an estimated pe- Visual Binary Stars, U.S. Naval Observatory, riod of more than 4000 years, this seems to be in er- online access July 2011. ror. [7] Burnham´s Celestial Handbook, R. Burnham, Jr., Dover Publications, New York 1978.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 24

Chico High School Students' Astrometric Observations of the Visual Double Star STF 1657

Jonelle Ahiligwo1, Clara Bergamini1, Kallan Berglund1, Mohit Bhardwaj1, Spud Chelson1, Amanda Costa1, Ashley Epis1, Azure Grant1, Courtney Osteen1, Skyla Reiner1, Adam Rose1, Emily Schmidt1, Forest Sears1, Maddie Sullivan-Hames1, and Jolyon Johnson2

1. Chico Senior High School, California 2. Gateway Science Museum, California State University, Chico

Abstract: In the spring of 2011, Chico Senior High School students participated in an astronomy seminar at the Gateway Science Museum, University of California, Chico. The observers used a Celestron NexStar 6 SE telescope and a Celestron MicroGuide eyepiece to determine the separation and position angle of the visual double star STF 1657. Observa- tions were made in approximately one hour on the evening of May 1, 2011. The observers determined that the separation of STF 1657 was 22.1” and the position angle was 273.4°. Seminar members then used the spectral type, parallax, and proper motion vectors of the two stars to determine if they are a line-of-sight optical pair or physically bound by gravity. Due to large errors in the parallax and the proper motion vector for the secondary star, the results were inconclusive. Through this experience, the students learned the skills needed to observe, analyze, and report on double stars.

Introduction In the spring of 2011 Jolyon Johnson led an astronomy research seminar of fourteen enthusiastic students from Chico Senior High School, California. The seminar was offered through the Gateway Sci- ence Museum at California State University, Chico, and focused on the study of visual double stars. It followed a model developed at Cuesta College in San Luis Obispo, California and the University of Ore- gon's Pine Mountain Observatory (Johnson 2007, Genet et al. 2010a, Genet et al. 2010b). The goals of the seminar were both scientific and educational. The scientific goals were to: 1) contrib- Figure 1: Students gathered at the Gateway Science Museum on ute observations to the Washington Double Star the evening of May 1, 2011 to observe the double star STF 1657 (WDS) catalog, and 2) determine whether or not this with a Celestron NexStar 6 SE telescope and a Celestron Mi- double star is likely a chance optical line-of-sight croGuide eyepiece.

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Chico High School Students' Astrometric Observations of the Visual Double Star STF 1657

double or a binary star bound by gravity. The educa- from the linear scale because of polar misalignment. tional goals were to: 1) gain a better understanding of The mean distance in divisions was multiplied by the astronomy through hands-on experience, 2) learn and scale constant of 12.3 arc seconds per division to con- apply a method for measuring the separation and po- vert the measured value into arc seconds. The stu- sition angle of a double star, and 3) learn the process dents then calculated the standard deviation and for analyzing data and writing and editing a scientific standard error of the mean of this separation. paper. The drift method was used to measure the position angle between celestial north and the secondary Methods star with the primary star at the vertex (Teague The students searched the WDS catalog to iden- 2004). First the primary star was centered at the mid- tify observable stars based on their magnitude and point of the linear scale and the eyepiece was rotated separation. The stars had to be bright enough and far until the secondary star was between the parallel enough apart to observe in a 6-inch telescope and lines of the scale. The RA motor was then disabled bright city skies. The visual double star STF 1657 fit and the stars drifted toward the outer protractor. the criteria with a primary magnitude of 5.1, a secon- Where the primary star crossed the protractor was dary magnitude of 6.3, and separation of 19.9 arc sec- noted to the nearest degree and secretly told to the onds (Mason 2008). Observations were made on May recorder to avoid bias. A 90° position angle correction 1, 2011 (B2011.353) with a Celestron NexStar 6 SE was added to the measurements as is required for the telescope and a 12.5 mm illuminated Celestron Micro Celestron MicroGuide eyepiece (Teague 2004). A total Guide eyepiece. of 10 measurements were made and their average, Several past seminars have used the same tele- standard deviation, and standard error of the mean scope and eyepiece as the present study to observe were calculated with one outlier rejected because it double stars. The scale constants they derived were was more than three times the standard deviation. averaged and used in the present study. Table 1 The outlier was precisely 20° off and likely the result shows the three scale constants used, their average, of misreading major divisions. standard deviation, and standard error of the mean. The mean error of 0.1”/div is significantly less than Observational Results the mean observational error. Table 2 shows the results of the separation and The separation of the two stars was estimated to position angle measurements including the averages, the nearest 0.1 division on the linear scale (Teague standard deviations, standard errors of the mean, and 2004). Each student noted at least one observation the average of three catalog values, the first and last and whispered it to a designated recorder so others from the WDS Catalog and one from Eagle Creek Ob- could not hear, thus preventing bias. A total of 12 servatory (Mason 2008 and Muenzler 2003). measurements were made. Three outliers were ex- The difference between the observed and average cluded from the mean because they were more than catalog separation value of 1.8” is higher than would three times the standard deviation from the average. be expected—four times the standard error of the These outliers were due to the stars drifting away

Table 1 : The measured scale constants of past re- Table 2: The averages, standard deviations, and stan- search seminars using the NextStar 6 SE and Celestron dard errors of the mean for the separation and position Microguide eyepiece used in the present study. angle compared to catalog values. Scale constant

(arc seconds per division) Separation Position Angle

Baxter et al. 2011 12.2 Observed Catalog Observed Catalog

Brashear et al. 2011a 12.5 Average 22.1” 20.3” 273.4° 272°

Brashear et al. 2011b 12.2 St. Dev. 1.2” 0.4” 0.5° 1.7°

Average 12.3 Mean Err. 0.4” 0.2” 0.2° 1.0°

St. Dev. 0.2

Mean Err. 0.1

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Chico High School Students' Astrometric Observations of the Visual Double Star STF 1657

mean of 0.4”. The maximum for the catalog values is likelihood that the stars are bound by gravity. still 0.2” different from the minimum observed value. Finally, the students analyzed the proper motion If the minimum scale constant of 12.2”/div is used, the vectors of the two stars to determine if they are trav- average separation is 22.0”. This is still four times the eling through space in approximately the same direc- standard error of the mean away from the average of tion. Most binary star components have proper mo- catalog values. The authors attribute the difference tion vectors within 10% of each other (Arnold 2010). primarily to polar misalignment (which caused the Table 3 shows the proper motion vectors of the two stars to drift away from the linear scale) or other sys- stars of STF 1657. tematic errors. While the vectors appear different, the errors for The observed position angle was also significantly the secondary star are very large, 25.11 mil- different from the average catalog value. The differ- liarcseconds per year (mas/yr) in RA and 15.97 mas/yr ence of 1.4° is 7 times the standard error of the mean in dec. Thus the secondary star could be traveling as of 0.2°. However, there is overlap between the maxi- slow as -0.29 mas/yr in RA and as high as 28.75 mas/ mum catalog values and minimum observed value. yr in dec. Additionally, the error in RA for the pri- The difference may have been caused by an imprecise mary star is 2.12 mas/yr giving a maximum value of - alignment of the stars on the linear scale. 2.46 mas/yr. With the errors taken into account, the two stars can be shown to travel essentially in the System Analysis same direction through space. Yet, this can only be The students referenced the SIMBAD (2011) da- done with the extremes of the uncertainties, making tabase to determine whether or not the stars could be it possible, though unlikely, that the stars are moving a gravitationally bound binary. The pair of stars se- in the same direction. lected has the WDS designation of STF 1657, which corresponds to HD 109511 and HD 109510 for the Table 3: Proper motion vectors for the primary primary and secondary stars, respectively. To deter- and secondary stars mine if it is possible that the two stars are bound by gravity, we first compared the spectral types and ap- RA (mas/yr) Dec (mas/yr) parent magnitudes of the two stars. The primary star HD 109511 -4.58 23.30 is spectral type K2III and has a primary magnitude of 5.11, making it likely to be a red giant. The secondary HD 109510 24.82 12.78 star is on the main sequence with spectral type A9V at magnitude 6.33. It is difficult to estimate how bright a red giant should be compared to an intrinsi- cally bright main sequence star, so a more quantita- Conclusions tive analysis had to be made. Due to the large error margins reported for the The group then attempted to calculate the actual trigonometric parallax and proper motion vectors in distance to the two stars from Earth based on their the SIMBAD database for HD 109510, it is uncertain respective trigonometric parallaxes. The distance in whether or not the system is bound by gravity. More light years can be calculated as the inverse of the par- precise parallax and proper motion vectors may help allax in arc seconds multiplied by 3.26 (the number of determine if the stars do, in fact, orbit one another. If light years in one parsec). The parallax of the primary this is proven, continued research may yield the semi- star is 0.00531 arc seconds which corresponds to a major axis, orbital period, and stellar masses. Though distance of 614 light years. The parallax of the secon- it could not be determined if the system was binary, dary star is 0.00124 arc seconds which corresponds to the seminar proved a valuable learning experience. a distance of 2,629 light years. While this would cer- The students also learned some frustrations asso- tainly suggest the stars are not bound by gravity, the ciated with astronomical observing. For example, the error statement of the secondary star's parallax is prime observing time happened to be the evening be- 0.00991 arc seconds. The secondary star could be infi- fore a full moon so a new observing night had to be nitely far away (since there cannot be a negative par- scheduled. This second evening was found to be allax the minimum value is 0.0 arc seconds) or as cloudy in local weather forecasts. Thus, the observing close as 292 light years. This range of values makes night had to be on a school night in May when astro- the calculated distance unreliable. Therefore, we nomical twilight did not occur until approximately could not use the distance estimates to determine the 9:00 and everyone had to leave by 10:00. Observations

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Chico High School Students' Astrometric Observations of the Visual Double Star STF 1657

had to be limited to just the double star unlike previ- cro Guide Eyepiece”, Journal of Double Star Ob- ous seminars that also determined the scale constant servations, 7, 212. for the linear scale. Once sufficient separation and Brashear, Nicholas, et al., 2011a, “Measurements and position angle measurements were taken, observing Analysis of the Visual Double Star STF 1919 at time was over. The students are hopeful that the the 2010 Oregon Star Party.” Journal of Double separation and position angle values they determined Star Observations, Submitted. may be added to the WDS catalog and used by future researchers if STF 1657 proves to be binary. Brashear, Nicholas, et al., 2011b, “Observations, On the evening of observations, the students Analysis, and Orbital Calculation of the Visual learned how to polar align the NexStar 6 SE, apply Double Star STTA 123 AB.” Journal of Double the astrometric vocabulary they learned during the Star Observations, Submitted. seminar, and avoid potential research biases. The fol- Genet, Russell, et al, 2010a, “One-Semester Astro- lowing meetings taught students how to turn simple nomical Research Seminars” in Small Telescopes measurements into meaningful data by using basic and Astronomical Research, Eds. Russ Genet, statistics. Finally, the students learned the tools as- Jolyon Johnson, and Vera Wallen, Santa Marga- tronomers use to identify binary stars and compiled rita, CA, Collins Foundation Press. the information into a research paper. Such skills are invaluable to high school and undergraduate students Genet, Russell, et al, 2010b, “Pine Mountain Observa- headed for careers in science. tory Summer Research Workshop” in Small Tele- scopes and Astronomical Research, Eds. Russ Acknowledgments Genet, Jolyon Johnson, and Vera Wallen. Santa The authors would like to thank the Gateway Sci- Margarita, CA, Collins Foundation Press. ence Museum at California State University, Chico and Director Rachel Teasdale for hosting the seminar. Johnson, Jolyon, 2008, “Double Star Research as a Form of Education for Community College and The students also thank Russ Genet at California th Polytechnic State University for advising the semi- High School Students” in Proceedings for the 27 nar, loaning the telescope used in the project, and for Annual Conference for the Society for Astronomi- reviewing the paper. The authors would also like to cal Sciences, Eds. Brian Warner, Jerry Foote, thank Celestron who donated the eyepiece, equatorial David Kenyon, and Dale Mais. wedge, and tripod to student research. The authors Mason, Brian, 2011, The Washington Double Star finally thank Dave Arnold and Tom Frey for their Catalog, Astrometry Department, U.S. Naval Ob- helpful reviews. servatory. http://ad.usno.navy.mil/wds/wds.html. References Muenzler, Kevin, 2003, “Double Stars in Coma Beren- ices.”, Eagle Creek Observatory. http:// Arnold, Dave, 2010, “Considering Proper Motion in www.eaglecreekobservatory.org/eco/doubles/ the Analysis of Visual Double Star Observations” com.html. in Small Telescopes and Astronomical Research. Eds. Russ Genet, Jolyon Johnson, and Vera SIMBAD Astronomical Database, 2011, Centre de Wallen, Santa Margarita, CA: Collins Foundation Données Astronomiques de Strasbourg, http:// Press. simbad.u-strasbg.fr/simbad/. Baxter, Alexandra, et al., 2011, “Comparison of Two Teague, Tom, 2004, “Simple Techniques of Measure- Methods of Determining the Position Angle of the ment” in Observing and Measuring Visual Double Visual Double Star 61 Cygni with a Celestron Mi- Stars, Ed. Bob Argyle. London, Springer.

Jonelle Ahiligwo, Clara Bergamini, Kallan Berglund, Mohit Bhardwaj, Spud Chelson, Amanda Costa, Ashley Epis, Azure Grant, Courtney Osteen, Skyla Reiner, Adam Rose, Emily Schmidt, Forest Sears, and Maddie Sullivan-Hames are physics students at Chico Senior High School. Jolyon Johnson is a senior geology major at California State University, Chico. He is a docent at the Gateway Science Museum and led the spring astronomy seminar.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 28

A New Companion for STF 2590, WDS 19523+1021

Micello Giuseppe

Bologna Emilia Romagna, Italy

[email protected]

Abstract: A new companion in Struve 2590 (WDS 19523+1021STF 2590) is described. This is a multiple star in the constellation Aquila and is composed of four components. The new component, identified in CCD images, is not present in the WDS.

in 2007 for pairs AB and CD. Introduction I consulted the articles published in the Journal On August 12, 2011 I ran some footage CCD to of Double star Observations (www.jdso.org) and make some routine astrometric measurements of found that Edgardo Rubén Masa Martin, in 2007, double stars in the W. Struve catalog. performed astrometric measurements for the AB and Consulting the Washington Double Star Catalog, CD pairs [Masa Martin, 2009]. In note 96, in the I noticed that STF 2590 (WDS 19523+1021, R.A. 19 same article, Masa states that component A is a vari- 52 15.58; DEC. +10 21 05.8) has four components, able star. but the CCD images show a new component E (Mv Figure 1 shows an image of STF 2590 with the E 13.5) for this multiple star system. component, obtained with Schmidt-Cassegrain tele- Methods scope 200/2000. For STF 2590, as shown in Table 1, the Washing- Astrometric Measurements and Data ton Double Star Catalog (WDS) lists the measures Analysis for the AB, AC and CD pairs, but no measurement The astrometric measurements were performed for an E component. CCD images, however, show a with the software REDUC (By Florent Losse) and star near the B component of this multiple star sys- the calibration star used was STF 2777 (WDS tem. The Aladin Sky Atlas (catalogs "SDSS-DR7, 21145+1000STF 2777; Theta: 6° - Rho: 74,1”). PPMXL, NOMAD1 e 2MASS-PSC") and the 2MASS- The telescope used was a Schmidt-Cassegarin PSC indicate that this star is “12521526+1021199” 200/2000 on German equatorial mount and the opti- with a visual magnitude of 13.5. cal train was composed of CCD Camera DMK 21AU The latest measures of the Washington Double with IR/UV cut filter. Star Catalog were made in 2000 for the pair AC and

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 29

A New Companion for STF 2590, WDS 19523+1021

Table 1: Astrometric measurements of STF 2590 from the WDS

Coordinate WDS Name Theta Rho Mv1 – Mv2 Epoch ID WDS R.A. DEC.

STF 2590 AB 309° 13.5” 6.50 - 10.31 2007 19 52 15.58 +10 21 05.8 19523+1021

STF 2590 AC 309° 115.3” 6.50 – 11.6 2000 19 52 15.58 +10 21 05.8 19523+1021

STF 2590 CD 272° 8.3" 11.6 – 12.2 2007 19 52 09.50 +10 22 18.3 19523+1021

Figure 1: Image of STF 2590 showing the E component. Image by the author.

As shown in Table 2, I updated the measurements proper motion for this star is reported in the 2MASS- for the pairs AB, AC and CD and performed, for the PSC, NOMAD1 and PPMXL catalogs. first time, the measurements for the pair AE: Theta: The SDSS-DR7 catalog, indicates the component = 342.34° and Rho = 15.057” E as: “class 6 = Star: A a self-luminous gaseous celes- The catalog 2MASS-PSC catalog gives the quality tial body”. Figure 2 gives the astrometric data from flag "AAA", indicating the best quality JHK magni- the SDSS (Sloan Digital Sky Survey - http:// tudes which are: J - H - K = 12.608 - 12.352 - 12.328 cas.sdss.org/astro/en/tools/explore/). and a visual magnitude of 13.5. Unfortunately, no (Continued on page 31)

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A New Companion for STF 2590, WDS 19523+1021

Table 2: New astrometric measurements of STF 2590 AB, AC, and CD. First measurements new pair AE and probable new name.

Name and Mv1 – Mv2 Coordinate WDS Theta Rho Epoch ID WDS WDS R.A. DEC.

STF 2590 AB 309.5° 13.55” 6.50 - 10.31 2011.6113 195215.58 +102105.8 19523+1021

STF 2590 AC 309.3° 114.09” 6.50 – 11.6 2011.6113 195215.58 +102105.8 19523+1021

STF 2590 CD 272.1° 8.21” 11.6 – 12.2 2011.6113 195209.50 +102218.3 19523+1021

Coordinate WDS New Pair AE Theta Rho Mv1 – Mv2 Epoch R.A. DEC.

AE 342.3° 15.05” 6.50 - 13.5 2011.6113 195215.58 +102105.8 (19523+1021)

Figure 2: Screen shot of SDSS astrometric data on the new E component.

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A New Companion for STF 2590, WDS 19523+1021

References (Continued from page 29) Conclusions Brian D. Mason, Gary L. Wycoff, and William I. Hart- kopf. Washington Double Star Catalog - http:// One of the main questions is why has the E com- ad.usno.navy.mil/wds/ ponent not been cataloged? The article by Masa E. R. indicates the A component is a variable star, there- The Aladin Sky Atlas - http://aladin.u-strasbg.fr/ fore it may be that the E component was not seen for aladin.gml the variability of the principal component. But a vari- Sloan Digital Sky Survey - http://cas.sdss.org/astro/ able star may be the same component E, object of en/tools/explore/ study for the next steps. Masa E. R., 2009 “CCD Double-Star Measurementsat Acknowledgments Observatorio Astronómico Camino de Palomares I thank the Washington Double Star Catalog and (OACP): First Series” , JDSO, 5, 18, 2009. the Journal of Double Star Observations for the information. I thank Florent Losse for excellent software Reduc. This work made use of the catalogs of The Aladin Sky Atlas. A special thanks to Adriano Dragone for the help and advice.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 32

Divinus Lux Observatory Bulletin: Report #24

Dave Arnold

Program Manager for Double Star Research 2728 North Fox Run Drive Flagstaff, AZ 86004

Email: [email protected]

Abstract: This report contains theta/rho measurements from 109 different double star systems. The time period spans from 2010.616 to 2011.679. Measurements were obtained using a 20-cm Schmidt-Cassegrain telescope and an illuminated reticle micrometer. This report represents a portion of the work that is currently being conducted in double star astronomy at Divinus Lux Observatory in Flagstaff, Arizona.

This article contains a listing of double star nents, since 2001, is the cause for this shift. measurements that are part of a series, which have Two additional variances in the theta values for been continuously reported at Divinus Lux Observa- two more double stars are being noted. First, proper tory, since the spring of 2001. Beginning with this motion by the “A” component, for the BU 483 multi- article, the selected double star systems, which ap- ple star system, appears to have caused significant pear in the table below, have been taken exclusively increases in the theta values for AC and AD during from the 2006.5 version of the Washington Double the past 10 years. Increases of over three degrees are Star Catalog (WDS), with published measurements being reported for both components. Secondly, the that are no more recent than ten years ago. There theta value for STF 140 AC, which appears in the are also some noteworthy items that are discussed, table, is 2.5 degrees greater than the 1998 WDS which pertain to a few of the measured systems. value. Proper motion doesn’t appear to be the cause As in previous articles, this report contains some in this case, but since this double star has few previ- double stars with noteworthy theta/rho shifts be- ous measurements, perhaps additional measure- cause of the effects of proper motion by one or both of ments will help bring more accuracy to this parame- the components. To begin with, proper motion by ter. In a similar context, the rho measurement in both component stars, for ES 1015 AB, has caused a this report, for HJ 3437, lines up more closely with 4% rho value increase during the past decade. Like- the listing for 1836 than it does for the one in 2002. wise, proper motion by both components, for STF Additional measures of this pair might also be useful 2944 AC, is responsible for a 4% rho value increase, Some possible corrections are being suggested for but this occurred in just the last 5 years. Next, the 2006.5 version of the WDS catalog. First of all, proper motion by the companion star, for GRV 440, the 2005 theta value for STF 3008 (23238-0828) caused a 2 degrees theta value decrease during the might contain a typo, since the proper motion vectors past 10 years. A rho value decrease of 5% is being imply a theta value increase rather than a decrease. reported for HJ 1927. Proper motion by both compo- Based upon measurements for this report, it appears

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Divinus Lux Observatory Bulletin: Report #24

that this value might be 159 degrees instead of 150 to either confirm the 2001 catalog values or the ones degrees. Secondly, the 2000 theta value for HJ 5547 obtained for this report. (22204+1102) reveals a 2 degrees increase from the In a similar context, the historical data in the 1991 value, when the proper motion vectors suggest WDS catalog seems to suggest a position angle in- just the opposite. The theta measurement appearing crease, over time, for S 799AB (21434+3817) but the in this report seems to validate a decreasing theta position angle measurement obtained for this article value. is more closely in line with the value listed for 1824. Another unexplained discrepancy from catalog Again, others may want to consider making addi- values pertains to STF 431 (03424+3358). The WDS tional position angle measurements of this pair in catalog lists the parameters for this double star as order to help verify the actual value. 249 degrees and 25.6” in 2001, but measurements of Finally, the rho measurement in the catalog for this pair on 2010.847 yielded theta/rho values of ARY 9 (00116+5813), for 2002, appears to possibly be 243.8 degrees and 19.75 seconds. Proper motion shifts in error. The rho measurement in this report, for this are not significant enough to account for this and no double star, is much more closely aligned with the other pairs with similar parameters or magnitudes measurements in 1910, rather than the 2002 meas- appear in this part of the sky. Perhaps other re- urements. searchers might consider measuring this double star

NAME RA DEC MAGS PA SEP DATE NOTES STF2688 20308+1347 9.2 10.4 174.3 7.67 2010.616 1 GRV 440 21157+2355 10.6 10.6 297.9 43.94 2010.616 2 ES 1012 21467+5523 10.5 10.6 5.5 4.44 2010.616 3 ES 1015AB 21584+5245 10.4 10.7 238.7 7.90 2010.616 4 POP 145AB-CD 22042+4633 9.5 9.8 94.1 30.61 2010.616 5 STT 465 AB 22120+5012 7.3 10.5 317.3 12.84 2010.616 6 BU 477 22159+3125 9.5 10.3 40.8 6.42 2010.616 7 HJ 5547 22204+1102 7.5 10.1 300.9 40.98 2010.616 8 STF2944AC 22478-0414 7.2 8.5 87.1 60.24 2010.616 9 STF3008 23238-0828 7.1 7.6 159.2 5.93 2010.616 10 ARG 47 00027+5958 9.3 10.3 290.4 9.88 2010.638 11 HJ 1927 00032+4508 9.1 10.1 73.4 9.88 2010.638 12 BU 483AC 00091+4051 6.9 7.5 270.4 158.00 2010.734 13 BU 483AD 00091+4051 6.9 10.4 275.3 227.13 2010.734 13 HJ 1953AC 00194-0849 3.5 10.3 190.7 107.14 2010.638 14 HJ 1981A-BC 00310-1005 6.9 8.4 88.1 78.51 2010.638 15 STF 104 01170+3828 7.9 9.8 321.6 13.33 2010.638 16 HDO 45 01172+0201 7.2 9.5 102.6 38.02 2010.638 17 H 23AC 01201+5814 5.0 7.0 231.0 134.30 2010.638 18 H 23AD 01201+5814 5.0 10.2 287.8 178.74 2010.638 18 H 23AE 01201+5814 5.0 10.3 239.0 170.84 2010.638 18 H 23CE 01201+5814 7.0 10.3 265.3 41.97 2010.638 18

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Divinus Lux Observatory Bulletin: Report #24

NAME RA DEC MAGS PA SEP DATE NOTES WEI 3 01201+3639 8.9 9.7 188.4 4.94 2010.638 19

S 398 01284+0758 6.2 8.0 99.5 69.13 2010.658 20 HJ 2052 01316-1901 6.8 7.4 113.9 80.98 2010.658 21 STF 135AB-C 01341+3612 8.0 10.5 260.4 7.90 2010.658 22 STF 135AB-D 01341+3612 8.0 10.6 51.0 50.86 2010.658 22 STT 33AB 01374+5838 7.3 8.8 77.1 26.66 2010.658 23 DOB 2AC 01374+5838 7.3 10.2 109.3 106.65 2010.658 23 STF 140AC 01390+4104 9.2 9.9 322.5 195.53 2010.734 24 STF 150 01434-0705 7.7 8.2 195.8 36.04 2010.658 25 ENG 8 01496-1041 4.7 6.7 250.4 183.68 2010.658 26 STF 4AB 01562+3715 5.7 5.9 297.5 202.44 2010.658 27 BU 1368Bb 01562+3715 5.9 9.6 258.2 204.41 2010.658 27

STF 245Aa-B 02186+4017 7.2 8.0 293.9 11.36 2010.658 28

STT 27AB 02268+1034 6.7 8.3 31.9 73.57 2010.658 29 STF 431 03424+3358 5.0 10.0 243.8 19.75 2010.847 30 WEB 4 05290-0442 9.8 10.0 232.9 47.89 2010.978 31 STF 785AB 05459+2555 7.3 8.3 347.8 14.32 2010.978 32 STT 116AD 05459+2555 7.3 10.2 10.5 201.45 2010.978 32 BU 93AB 05489+2101 9.0 10.2 122.1 60.24 2010.978 33 H 125AB 05506+5655 6.5 10.4 128.0 26.19 2010.978 34 BRT1188 05596+1312 10.0 10.1 354.6 5.43 2010.978 35 GUI 10AC 06117+1723 7.5 9.0 35.9 73.08 2010.978 36

STF 889AB 06199+2501 7.4 9.9 243.2 21.23 2010.978 37

WAL 43AC 06199+2501 7.4 10.1 322.2 38.51 2010.978 37

A 2720AC 06234+1432 9.3 9.6 28.6 67.15 2010.978 38

STF1174AB-C 08047+4717 8.9 9.3 215.0 5.93 2011.118 39

WFC 81 09133+0540 10.2 10.4 76.5 8.39 2011.118 40

A 2367AB 10100+1623 9.9 10.6 85.0 60.74 2011.118 41

STF1435 10280+1950 10.3 10.7 203.2 8.89 2011.173 42

STF1442 10320+2202 8.2 8.5 156.8 13.33 2011.118 43

STF1447 10338+2321 7.5 8.8 124.4 4.44 2011.118 44

BU 111AC 10512-0906 10.0 9.4* 130.7 64.19 2011.173 45

STF3072 11309-0643 7.7 9.9 331.1 9.88 2011.173 46

ES 626 15409+5009 9.2 9.2 275.1 7.90 2011.367 47 STF 29AB 16224+3348 5.2 5.4 164.2 356.49 2011.367 48

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Divinus Lux Observatory Bulletin: Report #24

NAME RA DEC MAGS PA SEP DATE NOTES WEB 6 16354+1703 6.4 7.3 359.2 157.01 2011.411 49

STF 32AC 16579+4722 7.8 7.9 259.9 111.59 2011.367 50 STF 2156 17240-0050 9.0 9.4 35.0 3.95 2011.411 51 AG 210 17378+2257 9.9 10.2 187.5 4.44 2011.367 52 H 50AC 18497-0555 6.0 8.1 171.2 110.60 2011.411 53 STT 178 19153+1505 5.6 7.6 268.2 89.86 2011.501 54 STF 40AB 19188+0020 6.4 6.7 316.6 426.60 2011.501 55 STF 2498AB 19202+0403 8.1 8.8 66.1 11.85 2011.501 56 BOT 2AC 19202+0403 8.1 10.1 101.2 171.83 2011.501 56 STT 182AB 19268+5009 7.4 8.6 297.5 73.08 2011.501 57 HU 342 19371+1723 9.7 10.3 254.3 4.44 2011.501 58 STF 45AB 19431-0818 7.1 7.5 146.9 97.76 2011.501 59

ARY 23AB 20133+3502 8.4 8.8 28.3 80.98 2011.559 60

ARY 23BC 20133+3502 8.4 10.5 339.8 65.18 2011.559 60 ARY 1 20198+3707 6.6 8.5 257.3 77.03 2011.559 61 SHJ 323AD 20289-1749 4.9 6.6 149.8 258.73 2011.559 62 S 752AC 20302+1925 6.8 7.3 288.0 106.65 2011.559 63 ES 667 20386+4438 9.7 10.3 184.9 9.88 2011.556 64 STT 533AC 20391+1005 5.1 8.5 100.2 212.31 2011.556 65 STF 54AD 21103+1008 4.7 6.1 151.7 335.75 2011.559 66 STF 2780Aa-C 21118+5959 6.1 8.9 210.7 120.48 2011.559 67

WAL 137AB-E 21118+5959 6.1 10.3 44.5 61.72 2011.559 67

STF 55AB 21238+3721 6.4 6.6 303.0 362.41 2011.556 68

S 799AB 21434+3817 5.7 7.0 58.9 149.11 2011.556 69

S 799AC 21434+3817 5.7 10.1 318.1 135.29 2011.556 69

STF 2822AD 21441+2845 4.7 6.9 43.8 197.50 2011.559 70

HWE 59AB 22015-1537 7.1 10.2 270.1 8.89 2011.559 71

HJ 5524AD 22015-1537 7.1 9.9 312.8 180.71 2011.559 71

HJ 5355AB 22386-1404 7.5 8.7 289.3 83.44 2011.559 72

HJ 5355AC 22386-1404 7.5 9.2 359.3 106.65 2011.559 72

BU 1144Aa-BC 22430+3013 2.9 9.8 338.0 93.32 2011.559 73

STF 59AB-C 23052-0742 5.4 7.1 149.6 253.79 2011.674 74

S 823AC 23097+5920 5.7 8.2 162.8 166.89 2011.674 75

STF 2991 23134+1104 5.9 10.0 358.8 33.08 2011.674 76 ES 2725AB 23191+4855 7.2 8.5 235.0 54.31 2011.674 77

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Divinus Lux Observatory Bulletin: Report #24

NAME RA DEC MAGS PA SEP DATE NOTES HJ 5413AB 23418-1749 4.8 8.5 4.2 118.50 2011.674 78

STF3054 00031+0816 8.1 9.0 181.3 33.58 2011.677 79 HJ 1929AB-C 00039+2759 8.7 9.5 287.3 5.43 2011.677 80 ARY 7AB 00104+5831 7.7 8.3 2.7 124.43 2011.677 81 ARY 8AB 00108+5846 8.1 8.6 100.4 39.01 2011.677 82 ARY 8AC 00108+5846 8.1 8.3 42.8 104.68 2011.677 82 ES 2577 00112+4933 8.2 8.9 310.9 66.16 2011.677 83 ARY 9 00116+5813 7.1 8.5 82.7 138.30 2011.677 84 STF 8 00116-0305 7.8 9.2 291.1 7.90 2011.677 85 STF 17AB 00165+2918 8.3 9.8 29.6 27.16 2011.677 86 STF 28 00239+2930 8.3 8.5 224.0 33.08 2011.677 87 STT 10AB 00275+1602 6.4 10.1 239.9 113.56 2011.677 88

STT 10AC 00275+1602 6.4 9.3 156.0 274.53 2011.677 88

STF 49 00408-0714 7.0 9.8 321.5 8.72 2011.677 89 ES 224AC 00473+3837 9.4 10.4 108.6 66.66 2011.677 90 STF 70AB 00538+5242 6.3 9.4 247.2 8.39 2011.677 91 STF 72 00546+3910 8.2 9.1 173.3 23.70 2011.677 92 S 390 00582-1541 7.7 7.8 215.5 6.42 2011.677 93 BU 234AB 01005-1705 9.1 9.2 333.3 4.94 2011.679 94 BU 234AC 01005-1705 9.1 9.1 129.0 62.21 2011.679 94 HJ 2010 01027+4742 8.3 9.6 270.7 9.88 2011.679 95 STT 23AB 01101+5145 8.1 8.5 190.9 14.32 2011.679 96

ENG 4AB 01107+4256 7.7 9.9 308.4 152.08 2011.679 97

HJ 2030AC 01170+5345 8.6 9.1 193.1 38.51 2011.679 98

AG 17 01208+1127 8.3 10.3 98.5 54.81 2011.679 99

ES 1712AB 01243+5858 7.7 9.3 2.3 47.40 2011.679 100

ES 2583 01246+5311 8.2 9.1 344.6 26.17 2011.679 101

STT 30AC 01256+3133 8.0 8.0 105.7 56.78 2011.679 102

HJ 3437 01281-1716 7.4 9.3 247.3 12.34 2011.679 103

ARN 32AE 01433+6033 5.8 7.0 267.9 316.99 2011.679 104

HJ 644AC 01487+0741 7.1 9.7 226.2 128.38 2011.679 105

BUP 26Aa-B 01515-1020 3.7 10.0 40.1 188.61 2011.679 106

FRK 2 01564+3026 7.9 9.1 306.6 53.82 2011.679 107

A 819AB-C 01570+3101 7.7 9.9 271.2 66.66 2011.679 108 BU 7AC 01580-0204 6.6 8.8 199.0 152.08 2011.679 109

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Notes 28. In Andromeda. Common proper motion. Sep. & p.a. slightly inc. F3V, F3V. 1. In Delphinus. Sep. & p.a. increasing. Spect. 29. In Aries. Relatively fixed. Common proper G0. motion. Spect. A3, F0. 2. In Vulpecula. Position angle decreasing. 30. In Perseus. Position angle increasing. Spect. B1.5IV. 3. In Cygnus. Relatively fixed. 31. In Orion. Position angle increasing. Spect. M7, 4. In Cygnus. Separation increasing; position M. angle decreasing. 32. In Taurus. AB = sep. slightly increasing. AD = 5. In Lacerta. Separation slightly increasing. relatively fixed. Spect. B9. 6. Sep. & p.a. decreasing. Spect. F0II. 33. In Taurus. Common proper motion; p.a. 7. In Pegasus. Position angle decreasing. Spect. slightly decreasing. Spect. A0, G5. F5, F5. 34. In Camelopardus. Sep. increasing; p.a. de- 8. In Pegasus. Sep. increasing; p.a. decreasing. creasing. Spect. A4IV. Spect. K0. 35. In Orion. Common proper motion; p.a. 9. In Aquarius. Sep. increasing; p.a. decreasing. slightly decreasing. Spect. G2V, F5. 36. In Orion. Sep. decreasing; p.a. increasing. 10. Sep. and p.a. increasing. Spect. K0III, K0. Spect. B9.5III, F8. 11. In Cassiopeia. Position angle slightly increas- 37. In Gemini. AB = p.a. increasing. AC = sep. & ing. Spect. K, A0. p.a. increasing. Spect. K2. 12. In Andromeda. Sep. & p.a. decreasing. Spect. 38. In Orion. Position angle decreasing. Spect. F8, F5. F7V. 13. In Andromeda. AC & AD = sep. & p.a. in- 39. In Lynx. Relatively fixed. Common proper mo- creasing. Spect. A & C = G5, G5. tion. Spect. F5, F5. 14. 8 Ceti. Position angle decreasing. Spect. K0. 40. In Hydra. Common proper motion. Sep. & p.a. 15. In Cetus. Position angle slightly increasing. slightly increasing. Spect. G5. Spect. A5IV, G1V. 41. In Leo. Common proper motion. Sep. slightly 16. In Andromeda. Relatively fixed. Spect. G5. decreasing. Spect. G0, G5. 17. In Cetus. Sep. & p.a. increasing. Spect. G5. 42. In Leo. Sep. & p.a. increasing. Spect. G0, G. 18. Phi or 34 Cassiopeiae. All components rela- 43. In Leo. Separation decreasing. Spect. F0, A. tively fixed. Spect. AC = F5, B5. 44. In Leo. Common proper motion; p.a. slightly 19. In Andromeda. Common proper motion; sep. increasing. Spect. A2, A2. & p.a. inc. Spect. G0, G0. 45. In Sextans. Separation decreasing. Spect. of C 20. In Pisces. Relatively fixed. Common proper = F2. motion. Spect. K1III, G0. 46. In Crater. Relatively fixed. Common proper 21. In Cetus. Sep. increasing; p.a. decreasing. motion. Spect. F6V, F8. Spect. A7III, K0. 47. In Bootes. Separation decreasing. 22. In Andromeda. AB-C=fix.; c.p.m. AB-D=sep. 48. Nu Coronae Borealis. Separation decreasing. & p.a. dec. Spect. AB-C= A2. Spect. M2III, K5. 23. In Cassiopeia. AB = sep. & p.a. inc. AC = rel- 49. In Hercules. Relatively fixed. Common proper fix. Spect. AB = B3IV, K7. motion. Spect. A2V, A5. 24. In Andromeda. Separation increasing. Spect. 50. In Hercules. Relatively fixed. Common proper F2V, K0. motion. Spect. K8, K8. 25. In Cetus. Relatively fixed. Common proper 51. In Ophiuchus. Common proper motion; p.a. motion. Spect. A, A. increasing. Spect. F2, F2. 26. Chi or 53 Ceti. Relatively fixed. Common 52. In Hercules. Common proper motion; p.a. in- proper motion. Spect. F3III. creasing. Spect. M0V, M0. 27. 56 Andromedae. AB = sep inc.; p.a. dec. Bb = 53. In Scutum. Position angle increasing. Spect. relfixed. Spect. K0III, M0.

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K1II, K0. 78. 104 Aquarii. Sep. & p.a. decreasing. Spect. 54. In Aquila. Relatively fixed. Common proper G0I, F. motion. Spect. G8II, A0. 79. In Pisces. Relatively fixed. Common proper 55. In Aquila. Separation slightly increasing. motion. Spect. F0, F0. Spect. K0III, F0. 80. In Pegasus. Sep. increasing; p.a. decreasing. 56. In Aquila. AB = relfix; c.p.m. AC = relfix. Spect. F8. Spect. AB = G5II, K. 81. In Cassiopeia. Sep. & p.a. increasing. Spect. F, 57. In Cygnus. Sep. increasing; p.a. decreasing. A5. Spect. F6V, A5. 82. In Cassiopeia. AB = relfix, c.p.m. AC = relfix. 58. In Sagitta. Sep. & p.a. increasing. Spect. F8. Spect. B5, B9, B8. 59. In Aquila. Relatively fixed. Common proper 83. In Cassiopeia. Relatively fixed. Common motion. Spect. F4V, F5V. proper motion. Spect. A2, F0. 60. In Cygnus. AB = sep. inc. BC = p.a. dec. 84. In Cassiopeia. Separation increasing. Spect. Spect. AB = B0, F8. B5, G5. 61. In Cygnus. Separation increasing. Spect. A0, 85. In Pisces. Relatively fixed. Common proper K0. motion. Spect. F8, F8. 62. Rho or 11 Capricorni. Separation increasing. 86. In Andromeda. Separation increasing. Spect. Spect. F3V, K0. K0, A. 63. In Delphinus. Relatively fixed. Common 87. In Andromeda. Relatively fixed. Common proper motion. Spect. B7IV, B9. proper motion. Spect. G0, G0. 64. In Cygnus. Relatively fixed. Spect. K0. 88. In Pisces. AB = sep. inc. AC = p.a.inc. Spect. A5, F8, K2. 65. Kappa or 7 Delphini. Relfixed. Common proper motion. Spect. G1, K0. 89. In Cetus. Sep. increasing; common proper motion. Spect. G0, G0. 66. Gamma or 5 Equulei. Sep. & p.a. decreasing. Spect. A9V, A2. 90. In Andromeda. Separation increasing. Spect. A5. 67. In Cepheus. Aa-C & AB-E = p.a. slightly decreasing. Spect. B0II, B3, A0. 91. In Cassiopeia. Common proper motion; p.a. increasing. Spect. A0, A5. 68. In Cygnus. Separation decreasing. Spect. K5, F8. 92. In Andromeda. Position angle decreasing. Spect. M. 69. 79 Cygni. AB = sep. decreasing. AC = sep. increasing. Spect. AB = A0V, A0. 93. In Cetus. Common proper motion; p.a. increasing. Spect. F5, F5. 70. Mu or 1 Cygni. Sep. & p.a. decreasing. Spect. F7V, A5. 94. In Cetus. AB = sep. & p.a. inc. AC = sep. inc., p.a. dec. Spect. F0, F0, F0. 71. In Aquarius. AB = relfix, cpm. AD = sep. inc; p.a. dec. Spect. AB = G8, G8. 95. In Andromeda. Relatively fixed. Common proper motion. Spect. A0, A0. 72. In Aquarius. AB = sep. inc.; p.a. dec. AC = p.a. dec. Spect. A5II, F6V, M7. 96. In Cassiopeia. Relatively fixed. Common proper motion. Spect. F8, F8. 73. Eta or 44 Pegasi. Separation increasing. Spect. G0, G5. 97. In Andromeda. Position angle increasing. Spect. K0. 74. 83 Aquarii. Sep. decreasing; p.a. increasing. Spect. A9III, K0. 98. In Cassiopeia. Relatively fixed. Spect. F2, A. 75. 2 Cassiopeiae. Relatively fixed. Spect. A5III, 99. In Pisces. Relatively fixed. Common proper B8. motion. Spect. F8, K0. 76. In Pegasus. Sep. & p.a. slightly decreasing. 100. In Cassiopeia. Sep. & p.a. decreasing. Spect. Spect. G8III, G8III. K0. 77. In Andromeda. Sep. & p.a. increasing. Spect. 101. In Cassiopeia. Sep. decreasing; p.a. increas- A2, G5. ing. Spect. K2, K2. 102. In Pisces. Relatively fixed. Common proper

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Divinus Lux Observatory Bulletin: Report #24

motion. Spect. F8, G0. 103. In Cetus. Relatively fixed. Common proper motion. Spect. F0. 104. 44 Cassiopeiae. Relatively fixed. Spect. B9, K2. 105. In Pisces. Separation slightly increasing. Spect. K0. 106. Zeta or 55 Ceti. Position angle decreasing. Spect. K0, K0. 107. In Triangulum. Common proper motion; sep. slightly inc. Spect. F0, F0. 108. In Triangulum. Relatively fixed. Common proper motion. Spect. F5, G0. 109. In Cetus. Sep. & p.a. slightly increasing. Spect. A0, A0.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 40

Astrometric Measurements of Seven Double Stars, September 2011 Report

Joseph M. Carro

Cuesta College San Luis Obispo, California

Abstract: From my residence in Paso Robles, California, measurements of the separation and position angle of seven double stars were made. Listed in chronological order, the double stars were Zeta Ursae Majoris, Zeta Lyrae, Epsilon Delphini, SAO 105104 in Sagitta, STF 2840 in Cepheus, 61 Cygni, and 17 Cygni. The two goals of this project were to measure the position angle and separation of the aforementioned double stars, and to learn the necessary techniques to conduct this research.

Methodology My observations were made from my home in Paso Robles, California (located at approximately 35o37’36” N and 120o41’24” W) using a Celestron model CPC 1100 telescope (Figure 1). The telescope is computerized, motorized, and was fitted with a Celestron Micro Guide 12.5 mm astrometric eyepiece. The telescope is of Schmidt-Cassegrain de- sign, with aperture of 11 inches on an alt-azimuth mount. The manufacturer reports a focal length of 2,800 mm. The Micro Guide eyepiece was oriented with the celestial coordinate system using the primary star of the double star under study. The primary star was positioned on the mark 30, the drive was disabled, and the star was permitted to drift to the outer cir- cle. The scale was rotated until the star lay on the 270 degree mark. The accuracy of this setting was verified by positioning the primary star on the 90 degree mark of the outer circular scale, and allowing the star to drift to the 270 degree mark. Following the orientation, drift times were measured by placing the primary star on the 0 mark of the linear scale, and measuring the drift time from the 0 to the 60 mark using a stop watch precise to ±0.01 seconds. Measurements were made, and the Figure 1: The author with his Celestron telescope average drift time was calculated. That average was used to calculate the scale constant Z, using the for- mula14:

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Astrometric Measurements of Seven Double Stars, September 2011 Report

15.0411Tave cosδ Table 1: Literature Search; Separation (arc seconds); Z = Position angle (degrees) for Zeta Ursae Majoris D Reference name Sep PA

where Tave is the average time, δ is the declination 19 angle, and D is the number of reticle divisions. William Herschel Catalog 1779 data 14.3 153 Separation measurements were made by placing Washington Double Star Cat.35 1993 data 14.5 152

the pair of stars on the linear scale at the zero mark, 24 and then counting the number of scale divisions be- Eagle Creek Observatory 14.4 151 tween the stars. Because the scale has 60 divisions, it Daley, 200937 14.3 152.5 was only possible to estimate to the nearest ¼ division. After each measurement, the double star was Measurements by the author 2011 14.7 152.3 repositioned to the next major division. Measure- ments were made, and an average and standard de- ing at 11:50pm Pacific Daylight Time. The night was viation were calculated. clear and calm, and there was a ½ moon. The tem- The position angle measurements were made by perature ranged from 60 to 50o F. There was a breeze aligning both stars on the linear scale with the pri- of 5 – 10mph which affected the telescope and several mary star at the 30 division and pointing to the 60 measurements were repeated. mark, disabling the tracking feature, and then allow- The linear scale of the Micro Guide eyepiece was ing the stars to drift to the circular scales. The cross- oriented with the celestial coordinate system using ing of the primary star at the outer scale was approxi- the primary star. Once the orientation was com- mated to the nearest degree as the scale has divisions pleted, 12 drift time measurements were made, with of 5o. Following each measurement, the tracking fea- an average value of 47.19 seconds, a standard devia- ture was enabled and the process was repeated. tion of 0.63 seconds, and a standard error of the mean of 0.18 seconds. The result was a scale constant of 6.8 Zeta Ursae Majoris - Introduction arc seconds per division. This double star is located in the constellation of The primary star was placed on the linear scale, Ursa Major (the Great Bear), and is known by its tra- and 12 separation measurements were taken. The ditional name of Mizar with alternate spellings of average value was 2.2 divisions with a standard de- Mirzar, Mizat, and Mirza. This double star has been viation of 0.22 divisions, and a standard error of the known since ancient times, and was the first double mean of 0.06 divisions. When adjusted for significant star. On clear nights, the double star can be seen figures, the calculated separation was 14.7 arc sec- without the use of instruments. It was studied by onds. Benedetto Castelli in 1617, and has been studied fre- The position angle measurements were made us- quently since that time. Both stars are yellow with ing the aforementioned methodology, and 18 position magnitudes of 2.0 and 4.022. The colors reported for angle measurements were taken with an average this pair vary considerably having been reported as value of 152.3o, a standard deviation of 1.5o, and a both white, white and emerald, both green, blue, or standard error of the mean of 0.27o. yellow. For the AB components, Right Ascension is The separation value of 14.7 arc seconds and posi- 13h23m56s and the Declination is +54o55’31”. What tion angle value of 152.3o compared well with the was once thought to be a double star is actually a separation value of 14.5 arc seconds and the position complex of six stars which are all gravitationally angle value of 152o published in the Washington Dou- bound20. ble Star catalog.35 See Table 1. The catalog identifiers for this double star include 79 Ursae Majoris, ADS 8891AB, BD+55 1598A, BGC 18133, FK5 497, HD 116656, HIP 65378, HR 5054, Zeta Lyrae – Introduction SAO 28737, STF 1744, and WDS 13239+5456. Its Located in the constellation of Lyra (the Harp), precise coordinates are 132355.42+545531.5.22 the double star Zeta Lyrae has been known since ancient times. Its right ascension is 18h44m46s and its Zeta Ursae Majoris - Observations declination is +37o36’18”. The yellow primary and The measurements were made on 11 May 2011 blue-white secondary stars have magnitudes of 4.4 (Bessell date 2011.359) beginning at 9:50pm and end- and 5.7 respectively. Modern observations have

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Astrometric Measurements of Seven Double Stars, September 2011 Report

shown that Zeta Lyrae is a spectroscopic binary Table 2 Literature Review: Separation (arc seconds) and (Wikipedia). Position angle (degrees) for Zeta Lyrae The catalog identifiers for this pair include 6 Ly- rae, BD+37 3222, BU 968, CSV 101763, GSC Reference name Sep PA 03118+02080, HD 173648, HIP 91971, HR 7056, PPM Washington Double Star Cat.35 1835 data 43.7 150 81740, SAO 67321, STF 38, UBV 15954, and WDS 17 18448+3736. Its precise coordinates are Bright Star Catalog 43.7 - 22 184446.34+373618.2. Burton, 200610 43.6 150

Zeta Lyrae – Observations Perez, 200527 43.7 150

The measurements were made on 11 July 2011 Arnold, 20086 43.9 149.8 (Bessell date 2011.526) beginning at 10:15pm and 9 ending at 11:50pm Pacific Daylight Time. The night Bell, 2011 44 150 was clear, and the moon was gibbous. The tempera- Schlimmer33 2009 data 43.4 150.4 ture ranged from 60 to 50o F. The wind was gentle at 22 1 – 5mph. Washington Double Star Cat. 2010 data 43.7 150 The linear scale of the Micro Guide eyepiece was Measurements by the author 2011 44.0 149.8 oriented with the celestial coordinate system using the primary star. Once the orientation was com- 195482, HIP 101233, IDS 20264+1055, PPM 138507, pleted, 12 drift time measurements were made, with SAO 106195, SKY 38830, STF 2690, UBV M24917, an average value of 35.94 seconds, a standard devia- and WDS J20312+1116BC. Its precise coordinates tion of 0.29 seconds, and a standard error of the mean are 203111.94+111533.7.22 of 0.08 seconds. The result was a scale constant of 7.13 arc seconds per division. Epsilon Delphini – Observations The primary star was placed on the linear scale, The measurements were made on 1 August 2011 and 12 separation measurements were taken. The (Bessell date 2011.584) beginning at 9:30pm and end- average value was 6.17 divisions with a standard de- ing at 11:00pm Pacific Daylight Time. The night was viation of 0.25 divisions, and a standard error of the clear, with no moon. The temperature range was mean of 0.07 divisions. When adjusted for significant from 65 to 55o F. There was a 0 – 5mph breeze, and figures, the calculated separation was 44.0 arc sec- the humidity was 25%. onds. The linear scale of the Micro Guide eyepiece was The position angle measurements were made us- oriented with the celestial coordinate system using ing the aforementioned methodology, and 18 position the primary star. Once the orientation was com- angle measurements were taken with an average pleted, 12 drift time measurements were made, with value of 149.9o, a standard deviation of 2.18o, and a an average value of 28.91 seconds, a standard devia- standard error of the mean of 0.4o. tion of 0.28 seconds, and a standard error of the mean The separation value of 44.0 arc seconds and posi- of 0.08 seconds. The result was a scale constant of tion angle value of 149.9o compared well with the 7.11 arc seconds per division. separation value of 43.7 arc seconds and the position The primary star was placed on the linear scale, angle value of 150o published in the Washington Dou- and 12 separation measurements were taken. The ble Star catalog 22. See Table 2. average value was 2.5 divisions with a standard deviation of 0.0 divisions, and a standard error of the Epsilon Delphini - Introduction mean of 0.0 divisions. When adjusted for significant Located in the constellation of Delphinus (the Dol- figures, the calculated separation was 17.7 arc sec- phin), the double star Epsilon Delphini consists of a onds. pair of yellow-white stars of magnitudes 7.1 and 7.4. The position angle measurements were made us- For the AB components, the right ascension is ing the aforementioned methodology, and 18 position 20h31m12s and its declination is +11o15’34” 22. It does angle measurements were taken with an average not have a traditional name. value of 256o, a standard deviation of 1.5o, and a stan- The catalog identifiers for this pair include ADS dard error of the mean of 0.28o. 13946BC, AG+11 2505, BD+10 4307B, CSI+10 4307 The separation value of 17.7 arc seconds and the 1, GC 28544, GCRV 12819, GEN+1.00195482, HD position angle of 256o compared well with the values

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Astrometric Measurements of Seven Double Stars, September 2011 Report

Table 3: Literature Review, Separation (arc seconds) Table 4: Literature Review, Separation (arc seconds); o and Position angle (degrees) for Epsilon Delphini Position angle (in ) for SAO 105104 in Sagitta

Reference name Sep PA Reference name Sep PA

Washington Double Star Cat.22 1777 data 15.0 281 W. Herschel (McEvoy 2011)19 1796 data 28.2 302

The Hipparcos Catalog28 1997 data 16.7 253 Hipparcos Catalog28 30.0 301.2

Eagle Creek Observatory24 16.7 256 SKY2000 Master Catalog25 28.2 302

Arnold, 20065 17.8 254.8 C C D M Catalog13 28.2 302

Schlimmer, 200730 17.3 254.1 Arnold 20108 28.6 301.3

Schlimmer, 200932 17.7 254.8 Washington Double Star Cat.22 2010 data 28.6 301

Washington Double Star Cat.22 2009 data 17.3 255 Measurements by the author 2011 29.0 301

Schlimmer 201033 17.3 255.1 arc seconds per division.

15 The primary star was placed on the linear scale, The Tycho Catalog 17.4 254.8 and 12 separation measurements were taken. The Measurements by the author 2011 17.7 255.9 average value was 4.0 divisions with a standard deviation of 0.0 divisions, and a standard error of the of 17.3 and 255o as given in the Washington Double mean of 0.0 divisions. When adjusted for significant Star catalog 22. See Table 3. figures, the calculated separation was 29.0 arc seconds. SAO 105104 in Sagitta – Introduction The position angle measurements were made us- Located in the constellation of Sagitta (the Arrow) ing the aforementioned methodology, and 18 position is this double star of which the primary star is yellow- angle measurements were taken with an average orange and the secondary star is white. With magni- value of 301o, a standard deviation of 1.7o, and a stan- tudes of 6.4 and 9.5, the secondary star approached dard error of the mean of 0.31o. the limit of the CPC 1100 telescope. Its Right Ascen- The separation value of 29.0 arc seconds and posi- sion is 19h39m25s and its Declination is +16o34’16”22. tion angle value of 301o compared well with the sepa- This double star has no traditional name. ration value of 28.6 arc seconds and the position angle The catalog identifiers includeAG+16 2018, value of 301o published in the Washington Double BC+16 3936, GSC 01602-01582, HD 185622, JIP Star Catalog 22. See Table 4. 96688, HP 7475, IRAS 19371+1627, PPM 136711, SAO 105104, TYC 1602-1582-1, V 0340, and WDS STF 2840 in Cepheus – Introduction 1934+1634A. Its precise coordinates are Located in the constellation of Cepheus, this pair 193925.33+163416.0.22 of yellow stars has magnitudes of 5.6 and 6.4. STF 2840 in Cepheus has been well studied, but little has SAO 105104 in Sagitta – Observations been written about this pair. The WDS gives its These measurements were made on 3 August Right Ascension is 21h52m01s and its Declination is 2011 (Bessell date 2011.589) beginning at 9:30pm and +55o47’48”22, however, the Cambridge Double Star ending at 11:00pm Pacific Daylight Time. The night Atlas lists an R.A. of 21h52m19s and a Dec. of was clear, with a ¼ moon in the southwest. The tem- +55o50’10”, and the data from the Hipparcos Catalog28 perature range was from 65 to 55o F. There was a 0 – is an R.A. of. 21h52m00s and a Dec. of +55o47’31”. 5mph breeze. The humidity was 30%. The catalog identifiers include ADS 15045, AG+55 The linear scale of the Micro Guide eyepiece was 1503, BD+55 2638, HD 208063, HIP 107929, IDS oriented with the celestial coordinate system using 21486+5519B, PPM 39938, SAO 33817, SKY 41670, the primary star. Once the orientation was com- TYC 3972-2737-1, UBV 187420, and WDS pleted, 12 drift time measurements were made, with 21520+5548B. Its precise coordinates are an average value of 30.36 seconds, a standard devia- 215201.02+554748.322 tion of 0.15 seconds, and a standard error of the mean of 0.04 seconds. The result was a scale constant of 7.3

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Astrometric Measurements of Seven Double Stars, September 2011 Report

Table 5: Literature Review: Separation (arc seconds); Position Table 6: Literature Review, Separation (arc seconds) and Posi- angle (degrees) for STF 2840 in Cepheus tion angle (degrees) for 61 Cygni

Reference name Sep PA Reference name Sep PA 19 22 W. Herschel (MacEvoy 2011) 1753 Washington Double Star Cat. 1782 data 21.2 192 35 19.6 data Hipparcos Catalog28 1993 data 17.9 197 Bright Star Cat.17 28.7 - 35 24 Washington Double Star Cat. Eagle Creek Observatory 18.3 196 30.4 149 1993 data 8 The Hipparchos Catalog28 1993 Arnold 2010 17.8 196.8 31.6 151.2 data22 22 Washington Double Star Cat. 2010 data 17.8 197 Arnold 20064 2004 data 31.1 150.9

Measurements by the author 2011 18.1 196 Muller 200723 2005 data 31.6 152.6 STF 2840 in Cepheus – Observations Perez 200627 36 140 The measurements were made on 9 August 2011 Schlimmer 200931 2008 data 31.0 151.3 (Bessell date 2011.605) beginning at 10:20 pm and Heijen 200816 31.1 151 ending at 11:30 pm Pacific Daylight Time. The night was clear, calm, with a gentle breeze of 1 – 5 mph. Anton 20112 Oct 9 31.2 151.3 The moon was 2/3 full in the southwest. The tem- Anton 20112 Oct 12 31.35 151.6 perature ranged from 60 to 50o F. The humidity was Washington Double Star Cat.22 31.4 152 65%, and seeing was 3 - 4. 2010 data The linear scale of the Micro Guide eyepiece was Measurements by the author 2011 31.9 151 oriented with the celestial coordinate system using the primary star. Once the orientation was com- of about 5 arc seconds per year, and is sometimes pleted, 12 drift time measurements were made, with called the “Flying Star”39. In 1838 Bessell measured an average value of 51.55 seconds, a standard devia- the parallax and distance from the Earth for this pair, tion of 0.25 seconds, and a standard error of the mean which was the first double star to be so measured38. of 0.08 seconds. The result was a scale constant of 7.3 The orange pair is distinct, but the surroundings lack arc seconds per division. any prominent stars. The pair has magnitudes of 5.2 The primary star was placed on the linear scale, and 6.1. Its Right Ascension is 21h 06m 54s and its and 12 separation measurements were taken. The Declination is +38o 44’ 58” 22 average value was 2.5 divisions with a standard de- . viation of 0.0 divisions, and a standard error of the The catalog identifiers include BD+38 4343, FK5 mean of 0.0 divisions. When adjusted for significant 793, HD 201091, HIP 104214, HR 8085, GC 29509, figures, the calculated separation was 18.1 arc sec- GJ 820, PPM 86045, SAO 70919, STF 2758, UBV onds. 18287, and WDS 21069+3845. Its precise coordinates 22 The position angle measurements were made us- are 210653.94+384457.8. ing the aforementioned methodology, and 18 position 61 Cygni – Observations angle measurements were taken with an average The measurements were made on 14 August 2011 value of 196o, a standard deviation of 1.3o, and a stan- (Bessell date 2011.619) beginning at 8:45pm and end- dard error of the mean of 0.24o. ing at 9:30pm Pacific Daylight Time. The night was The separation value of 18.1 arc seconds and posi- clear and calm with no moon. The temperature tion angle value of 196o compared well with the sepa- ranged from 75 to 65o F. The humidity was 25%, and ration value of 17.8 arc seconds and the position angle seeing at 4 – 5. The wind at 5 - 10mph affected the value of 197o published in the Washington Double measurements, and many were repeated. Star catalog 22. See Table 5. The linear scale of the Micro Guide eyepiece was 61 Cygni – Introduction oriented with the celestial coordinate system using Located in the constellation of Cygnus (the Swan) the primary star. Once the orientation was com- is 61 Cygni, a famous pair of orange stars. First stud- pleted, 12 drift time measurements were made, with ied Piazzi in 1792, the pair has a large proper motion an average value of 36.17 seconds, a standard devia-

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Astrometric Measurements of Seven Double Stars, September 2011 Report

Table 7: Literature Review, Separation (arc seconds) 17 Cygni – Observations and Position angle (degrees) for 17 Cygni The measurements were made on 15 August 2011 (Bessell date 2011.622) beginning at 8:30 pm and end- Reference name Sep PA ing at 10:30 pm Pacific Daylight Time. The night was W. Herschel (MacEvoy 2011)19 1822 data 25.5 73 clear with moonrise at 9:30pm. The temperature ranged from 75 to 65o F. The wind was 1 - 5mph, hu- Starland Catalog (Olcott 1909)26 26.2 69 midity 30%, and seeing 3 – 4. Washington Double Star Cat.35 1993 data 26.3 69 The linear scale of the Micro Guide eyepiece was oriented with the celestial coordinate system using Hipparcos Catalog28 26.2 67.5 the primary star. Once the orientation was com- Eagle Creek Observatory24 26 70 pleted, 12 drift time measurements were made, with an average value of 33.84 seconds, a standard devia- Astrogeek (Burton 2011)10 2006 data 26.3 67 tion of 0.2 seconds, and a standard error of the mean Arnold 20107 26.2 69 of 0.06 seconds. The result was a scale constant of 7.1 arc seconds per division. Washington Double Star Cat.22 2009 data 26.2 69 The primary star was placed on the linear scale, Measurements by the author 2011 25.5 69 and 12 separation measurements were taken. The average value was 3.6 divisions with a standard de- tion of 0.37 seconds, and a standard error of the mean viation of 0.10 divisions, and a standard error of the of 0.09 seconds. The result was a scale constant of mean of 0.03 divisions. When adjusted for significant 7.07 arc seconds per division. figures, the calculated separation was 25.5 arc sec- The primary star was placed on the linear scale, onds. and 12 separation measurements were taken. The The position angle measurements were made us- average value was 4.5 divisions with a standard de- ing the aforementioned methodology, and 18 position viation of 0.1 divisions, and a standard error of the angle measurements were taken with an average mean of 0.03 divisions. When adjusted for significant value of 68.9o, a standard deviation of 1.35o, and a figures, the calculated separation was 31.9 arc sec- standard error of the mean of 0.25o. onds. The separation value of 25.5 arc seconds and the The position angle measurements were made us- position angle value of 69 degrees compared well with ing the aforementioned methodology, and 18 position the values of 26 arc seconds and 69 degrees from the angle measurements were taken with an average Washington Double Star Catalog22. See Table 7. value of 150.8o, a standard deviation of 1.3o, and a standard error of the mean of 0.31o. Acknowledgements The separation value of 31.9 arc seconds and the The generous assistance of Russell Genet was in- position angle value of 151 degrees compared favora- strumental in the execution of this work. Grateful bly with the values of 31.4 arc seconds and 152 de- thanks to John Baxter for his review of this paper. grees as published in the Washington Double Star Catalog (Mason+ 2011)22. See Table 6. References 17 Cygni – Introduction 1. Anton R., “Double and Multiple Star Measure- ments”, The Journal of Double Star Observations, Located in the constellation of Cygnus (the Swan), vol 6 no 3, July 2010 17 Cygni is a yellow pair of stars with magnitudes of 5.1 and 9.3. Its right ascension is 19h 46m 26s and its 2. Anton R., “Double and Multiple Star Measure- declination is +33o 43’ 39”.22 ments”, Journal of Double Star Observations, vol The catalog identifiers include ADS 12913A, 7 no 2, 2011 BD+33 3587, CSI+33 3587 1, GC 27369, HD 187013, 3. Arnold D. “Divinus Lux report #16”, Journal of HIP 97295, HR 7534, PLX 4654, PPM 83516, SAO Double Star Observations, vol. 5 no. 1 Winter 68827, STF 2580AB, TYC 2660-4227-1, and WDS 2009 19464+3344. Its precise coordinates are 194625.60+334339.3.22 4. Arnold D., “Divinus Lux Observatory: Report #3”, Journal of Double Star Observations, vol 2 no 2, 2006

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Astrometric Measurements of Seven Double Stars, September 2011 Report

5. Arnold D., “Divinus Lux Observatory: Report #6”, 21. Martín E, “CCD Double Star Measurements”, Journal of Double Star Observations, vol 2 no 3, Journal of Double Star Observations, vol. 5 no. 1 2006 Winter 2009 6. Arnold D., “Divinus Lux Observatory: Report #15”, 22. Mason B., Wycoff G., Hartkopf W., Douglass G., Journal of Double Star Observations, vol 4 no 4, Worley C., 2011, Washington Double Star Catalog 2008 23. Muller R., Cerosimo J., Miranda V., Martinez C., 7. Arnold D., “Divinus Lux Observatory: Report #20”, Cotto D., Rosado-de Jesus I., Centeno D., Rivera Journal of Double Star Observations, vol 6 no 1, L., “Observation Report 2005”, Journal of Double 2010 Star Observations, vol. 3 no. 2 Spring 2007 8. Arnold D., “Divinus Lux Observatory: Report #23”, 24. Muenzler K., 2003, Eagle Creek Observatory Journal of Double Star Observations, vol 6 no 4, (www.eaglecreekobservatory.org) 2010 25. Myers J., Sande C., Miller A., Warren W., Trace- 9. Bell, R., 2011, Stargazer Online, well D., 2002, Sky 2000 Master Star Catalog, God- www.richardbell.net dard Space Flight Center, Flight Dynamics Divi- sion. 10. Burton J., 2011, Astrogeek Observatory (www.astrogeek.org) 26. Olcott W., “In Star Land with a 3 inch Tele- 11. Daley J., “Double Star Measures for the year scope”, G. P, Putnam and Sons Publisher, 2005”, The Journal of Double Star Observations, 1909 vol 2 no 2, 2006 27. Perez J., Belt of Venus website 12. Daley J., “Double Star Measures for the year (www.perezmedia.net) 2005 2006”, The Journal of Double Star Observations 28. Perryman M., Lindegren L., Kovalevsky J., Hog vol 3 no 2, 2007 E., Bastian U., Bernacca P.L., Creze M., Donati 13. Dommanget J., Nys O., Catalogue des compo- F., Grenon M., Grewing M., van Leeuwen F., van santes d’étoiles doubles et multiples 2002 der Marel H., Mignard F., Murray C., Le Poole R., Schrijver H., Turon C., Arenou F., Froeschle M., 14. Frey T., “Visual Double Star Measurement with Petersen C., 1997, The Hipparcos Catalogue , an Alt-azimuth Telescope”, Journal of Double 2011 from its website www.rssd.esa.int Star Observations, vol 4 no 2 Spring 2008 29. SAO Staff, (1996) Smithsonian Astrophysical Ob- 15. Hog E., Baessgen G., Bastian U., Egret D., Fabri- servatory Star Catalog. cius C., Grossmann V., Halbwachs J., Makarov V., Perryman M., Schwekendiek P., Wagner K., 30. Schlimmer J., “Double Star Measurements Wicenec A., 1997, The Tycho Catalogue, 2011 Using a Webcam”, Journal of Double Star from its website www.rssd.esa.int Observations, vol 3 no 3, 2007 16. Heijen M., Star Observer website 31. Schlimmer J., “About Relative Proper Motion (www.starobserver.eu) 2008 of 61 Cygni”, Journal of Double Star Observa- 17. Hoffleit D., Warren W., 1991, The Bright Star tions, vol 5 no 2, 2009 Catalogue, 5th Revised Edition, Yale University 32. Schlimmer J., “Double Star Measurements 18. Johnson J., Genet R., “Measurements of the Dou- Using a Webcam: Annual Report of 2008”, ble Star STF 2079”, Journal of Double Star Obser- Journal of Double Star Observations, vol 5 no vations, vol 3 no 4 Fall 2007 2, Spring 2009 19. MacEvoy B., William Herschel’s Double Star 33. Schlimmer J., “Double Star Measurements Catalogs Restored, 2011 Using a Webcam: Annual Report of 2009”, 20. Mamajek E., Kenworthy M., Hinz P., Meyer Journal of Double Star Observations, vol 6 no M., “Discovery of a Faint Companion to Alcor Us- 3, July 2010 ing MMT Imaging”, Science Daily, 2009

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Astrometric Measurements of Seven Double Stars, September 2011 Report

34. Schupmann L., “Ludwig Schupmann Observatory Measures of Large Δm Pairs – Part Three”, The Journal of Double Star Observations, vol 5 no 3 Summer 2009 35. Worley C.E., Douglass G.G 1996, The Washington Visual Double Star Catalog 36. Worley C., Douglass G., 2006 The Washington Double Star Catalog 37. Daley J., Schupmann L., “Double Star Measures for the Year 2006”, Journal of Double Star Obser- vations, vol 3 no 2, 2009 38. Hirschfield A., “Parallax: the Race to Measure the Cosmos”, MacMillan Press 2001 39. Pannekoek A., “A History of Astronomy”, Courier Dover Publications, 1989

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Separation and Position Angle Measurements of Double Star STFA 46 and Triple Star STF 1843

Chandra Alduenda1, Alex Hendrix1, Navarre Hernandez-Frey2, Gabriela Key3, Patrick King4, Rebecca Chamberlain1, Thomas Frey5

1. The Evergreen State College, Olympia, Washington 2. Kentridge High School, Kent, Washington 3. St. Mary’s Academy, Portland, Oregon 4. Oregon Episcopal School, Portland, Oregon 5. California Polytechnic State University, San Luis Obispo, California

Abstract: Various students and faculty all participated in the 2011 4th annual summer astronomy workshop at Pine Mountain Observatory. Our group was trained in the proper techniques and skills required for measuring the separation and position angle of the binary star STFA 46 and trinary star STF 1843. We learned how to calibrate an astrometric eyepiece, make appropriate measurements, do a statistical analysis, and analyze data. The separation measurements our group made were comparable to current literature values. However, the observed position angles differed significantly from the literature. This discrepancy from literature values could be due to weather conditions or equipment limitations.

Introduction A group of students, three new and two experienced observers, and an instructor from The Ever- green State College (TESC) participated in the fourth annual astronomy research workshop at the Pine Mountain Observatory (PMO) near Bend, Ore- gon. This year’s topics were visual double star measurements and photometry. The workshop ran from July 24-28, 2011. All visual double star teams adopted team names; ours was “Dubhe or Not Dubhe”. The alt-az telescope used was an 18” Newtonian made by Ob- session. The Celestron Micro Guide 12.5 mm illuminated astrometric eyepiece was calibrated and then separation and position angle measurements were taken. On night two, group members Hernandez- Frey, Key, and King, along with experienced observ- Figure 1: Members of “Dubhe or Not Dubhe”. From left to right: ers Hendrix and Alduenda, joined their instructor Chandra Alduenda, Navarre Hernandez-Frey, Thomas Frey, Chamberlain and team leader Frey in observing dou- Patrick King, Gabriela Key, Alex Hendrix, Rebecca Chamberlain ble stars (DS). Since there were three members without DS observation experience, we decided to first

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Separation and Position Angle Measurements of Double Star STFA 46 AB and Triple Star ...

Table 1: Data for STFA 46 AB Table 2: Data for STF 1843 AB

Proper Motion Proper Motion (mas/

(mas/year) year) Star Parallax Right Spectral Star Parallax Right Spectral Declination Declination System (mas) Ascension Type System (mas) Ascension Type STFA 46A 47.44 -147.82 -159.01 G1.5Vb STF1843A 9.03 -46.84 -32.58 F5

STFA 46B 47.14 -135.11 -163.78 G3V STF1843B 13.87 -50.39 -35.71 F5

study the bright DS STFA 46 that had good separa- spectively (The SkyX). This indicates the star is an tion so they could understand the technique. Directly optical component of the AB system. after this, we observed the triple or trinary star (TS) STF 1843 in the constellation Bootes. The data was Locale and Observing Conditions analyzed and each student was assigned a topic to The study was carried out at Pine Mountain Ob- write up for the published paper. Alduenda and servatory near Bend, Oregon. The Observatory is lo- Hendrix were assigned to write a more extensive part cated at 43.79 degrees north latitude and 120.94 de- of the paper. grees west longitude. Due to high winds, humidity, and dew, the first night of observation was cancelled. Background The second night was more favorable with some The double star STFA 46 (also known as 16 breeziness at times that could have affected some Cygni) is actually a triple star system composed of an measurements. The seeing was good with only moder- AC-B combination. STFA 46 A (HD186408) has a ate scintillation. At times, the transparency was not close binary (16 Cygni C) first resolved by Turner favorable. (2001). The AC binary has a separation and position angle of 3.4 arc seconds and 209 degrees, respectively, Calibration of the Celestron Astromet- with a projected separation of 73 AU. The C compo- ric Eyepiece nent may be a red dwarf (Raghavan, 2006). STFA 46 The linear scale on the Celestron 12.5 mm astro- B has a Jupiter-mass planet orbiting the star with a metric eyepiece, divided into 60 equal divisions, must period of 2.2 years and an eccentricity of 0.69 (Mazeh, be calibrated for each telescope-eyepiece assembly to 1996). Due to the close agreement of parallax, proper determine the scale constant in arc seconds per divi- motion, and spectral types shown in Table 1, STFA 46 sion. This has been described at length previously AB is considered to be a binary pair (Hipparcos and (Frey, 2008). The reference star Navi (Gamma Cassio- Tycho, 1997), (Simbad database). peia) was used for this calibration because its declina- The triple star STF 1843 is in the constellation tion lies within the recommended 60-75 degree range Bootes. The parallax, proper motion and spectral type for calibration (Argyle, 2004). The results are given in for the A and B components are given in Table 2 Table 3. SD and ME are the standard deviation and (Hipparcos Catalog, The SkyX). the standard error of the mean. The values for proper motion and spectral type indicate a very close association for both A and B so Double Star STFA 46 Literature Values they likely both originated in the same collapsing gas Once the scale constant had been determined, cloud, indicating a possible binary relationship. The the 18-inch Obsession was two-star aligned and the parallax difference between A and B is converted to a tracking motors engaged. Because several of the ob- distance of 38.2 parsecs (124.3 light years). The C servers on the team were inexperienced in using an component is a G5 star with a right ascension and alt-az telescope, a well-studied double star was cho- declination proper motion of -43. 20 and +37.20, re- sen for initial study; STFA 46 in the constellation

Table 3: Scale Constant Determination

Scale Reference Besselian Declination Ave.Drift SD/ME # Observ. Constant Star Epoch (degs) Time(secs) (secs) (asec/div) Navi 2011.561 60.717 10 83.28 0.22/0.07 10.21

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Separation and Position Angle Measurements of Double Star STFA 46 AB and Triple Star ...

Table 4: Separation Measurements of STFA 46 and STF 1843.

Bessel. Literature SD/ME ObvSep LitSep Star System Identifier # Observ. Epoch Epoch (as) (as) (as) STFA 46AB 19418+5032 2011.56 2010 15 0.51/0.13 42.9 39.7

STF1843AB 14246+4750 2011.56 2007 10 0.54/0.17 20.9 19.8

STF1843AC 14246+4750 2011.56 2007 10 0.30/0.10 98.9 98.8

Table 5: Position Angle Measurements for STFA 46 and STF 1843.

Bessel. Literature SD/ME ObvPA LitPA Star System Identifier # Observ. Epoch Epoch (degs) (degs) (degs) STFA 46AB 19418+5032 2011.56 2010 15 3.35/0.87 130 133

STF 1843AB 14246+4750 2011.56 2007 10 4.64/1.47 180 187

STF 1843AC 14246+4750 2011.56 2007 10 3.36/1.01 59 64

Cygnus, first studied in 1800 and most recently in This method of moving stars to new locations along 2010 (Mason, 2009). The most recent Washington the linear scale for each measurement was made to Double Star (WDS) Catalog 2010 position angle and negate bias errors that might exist if the stars were separation values were 133 degrees and 39.7 arc sec- continually kept and measured at the same division onds, respectively. The primary and secondary magni- marks. tudes were 6.0 and 6.2. The right ascension and decli- Due to possible field rotation, the eyepiece was nation of the primary star are 19h 41m 49.1s and continually adjusted so that the two stars remained +50° 31m 31.6s. Table 1 gives additional data for aligned with the linear scale. The SD/ME are stan- STFA 46 AB. dard deviation and standard error of the mean. The observed and literature separations are given in arc Triple Star STF 1843 seconds. The separation measurements for STFA 46 The most recent study published in the WDS and STF 1843 are shown in Table 4. Catalog of the triple star STF 1843 ABC in the constellation Bootes was done in 2007, where the position Position Angle Measurements of STFA angle for the AB component was 187° and a separa- 46 and STF 1843 tion of 19.8 arc seconds. The primary and secondary The determination of the position angle using the stars had magnitudes of 7.68 and 9.23, respectively. drift method with the alt-az telescope has been de- The STF 1843 AC position angle was 64° with a sepa- scribed at length in a previous paper (Frey, 2008). ration of 98.8 arc seconds. The C component had a Briefly, it involves disengaging the servo-motors so magnitude of 9.72. Table 2 gives additional data for that the telescope becomes a “push Dob”. The double STF 1834 ABC. star is aligned with the linear scale and adjusted Separation Measurements of STFA 46 manually so, when the telescope is released, the primary star drifts through the 30th division mark on the and STF 1843 linear scale. This proper drift is difficult to do and The telescope was two-star aligned and the servo- usually takes several attempts to accomplish. Second, motors engaged. The Celestron Micro Guide eyepiece a parallax error can occur as the primary star crosses was rotated until the central linear scale was parallel the outer protractor scale that can lead to an errone- with the axis joining the two stars. The distances be- ous position angle. Third, aligning the two stars on tween the centers of the two stars was estimated to the linear scale becomes more challenging as the the nearest 0.1 divisions and recorded. Then, using separation becomes smaller. If not properly aligned, the slow motion controls, the stars were shifted to a the position angle will be radically altered. To circum- new location along the linear scale, and a new meas- vent these potential problems, 10-15 drift cycles were urement was made. We repeated this process 10-15 carried out, and the cycles averaged to obtain the best times, taking turns among all members of the group.

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Separation and Position Angle Measurements of Double Star STFA 46 AB and Triple Star ...

mean value. eyepiece was tightly held in place while being se- Due to possible field rotation, the eyepiece was cured, it could have rotated and thus be misaligned continually adjusted so that the two stars remained with the axis of the two stars. aligned as much as possible with the linear scale. The third and most likely explanation deals with Special effort was made to realign the stars parallel the separation between the two stars. This is espe- to the scale and the eyepiece tightened in the draw cially true of STF 1843 AB with a literature separa- tube. Position angles (PA) are given in degrees. The tion of 19.8 arc seconds. Because only the Celestron SD/ME are standard deviation and standard error of Micro Guide eyepiece was used to make the measure- the mean. The position angle measurements for STFA ments, the scale constant was 10.2 arc seconds per 46 and STF 1843 are shown in Table 5. division. So a 19.8 arc second separation spans less than 2 divisions on the linear scale. This is a very Discussion small distance to accurately align for the PA drift. Separation measurements on the two multi-star Whereas a slight misalignment of this span in meas- systems were carried out using only the Celestron uring separations would not affect the results signifi- Micro Guide eyepiece. Table 4 shows the observed and cantly, a small tilt in the alignment would make a most recent WDS literature separation values. If the significant error in the position angle value. See Fig- observed separation values are compared in the order ure 2. conducted, we see for STFA 46 AB, STF 1843 AB, and There are other possible reasons for position an- STF 1843 AC that the percent differences based on gle errors observed for STFA 46 AB, some of which the literature values were 8.1%, 5.5%, and 0.1%, re- can be traced to the recorded values themselves. spectively. Because three of the five students taking Eight of the fifteen values ranged between 130-133° measurements had never done this before, this de- and seven ranged from 122-129°. Seven different ob- creasing trend in percent error shows that the observ- servers recorded the 15 position angles in the course ers were learning observation techniques very rap- of the study. In some instances, one observer would idly. This is why it is wise to initiate beginning ob- begin the drift cycle (because adjusting the telescope servers with very bright and well-separated double to the proper drift position is very difficult for some) stars. and then switch off in mid-drift to another observer, The observed position angle measurements did who would watch the pair cross the protractor scale not correlate well with the literature values. There and announce the value. We now know this is an inef- are many possible reasons for these errors. The ob- fective procedure. There is the possibility that the served and literature values for the position angles observer could be watching the wrong star, that is, are shown in Table 5. The observed position angles the secondary instead of the primary. This is compli- for STFA 46 AB, STF 1843 AB, and STF 1843 AC dif- cated by the fact that the two stars have almost iden- fered from literature values by 4, 7, and 5 degrees, tical magnitudes; 6.0 and 6.2. This would change the respectively. Let’s account for some of these discrep- observed position angle to a whole new data set. If ancies. only the eight observations ranging from 130-133° First, weather may have contributed to these er- were considered, the mean position angle would have rors. Occasional breezes would occur during a PA been 131° with a standard deviation and mean error drift cycle enough to nudge the “push Dob” away from of 1.30 and 0.46, respectively. a proper drift. Yet, Grubbs Critical Value outlier for- The most severe difference between observed and mula (Burke, 1998) for a 99% confidence level deter- literature values of position angles occurred with STF mined that none of the collected data qualified as out- 1843 AB. As indicated in Figure 2, the 19.8 arc second liers but errant breezes could have moved the tele- separation makes alignment for the drift procedure scope enough to alter the observed position angle. especially challenging. There were ten recorded posi- Second, to cancel out possible field rotation and tion angles ranging from 175-186° and the literature bias readings, the eyepiece was rotated and realigned value was 187°. Because all of the observed values after several drift cycles. In the realignment process, were less than the literature value, the latter was re- the eyepiece was rotated so the linear scale was co- checked. WDS values indicated the position angle in aligned with the axis passing through the two stars 1830 and 2007 both having 187°. TheSkyX value was and the eyepiece was tightened with a set-screw on 186° 37 minutes, showing close agreement. The re- the draw tube. During the securing of the set-screw, corded position angles were reviewed again to make the eyepiece had a tendency to rotate. So unless the

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alignment of the pair of stars on the linear scale. This should only be done, however, when the atmospheric conditions are con- ducive. In the case of this study, the breeze factor was too great to allow use of the Bar- low. Also, since moderate scintillation was present it would make alignment and reading of both separation and position angle difficult. Second, limit the number of peo- ple doing a particular measurement to one observer. For this workshop the exercises and measurements carried out were for education and training. However, allowing more than one person to take a particular reading could have resulted in faulty results. Student Reflections Three of the five students making double star observations had never attempted this Figure 2: Possible Position Angle Errors Due to Misalignment on Linear Scale kind of science research before. Their ef- forts included instrument setup, orientation, instruction, making observations, sure that the data was correct. Six of the ten values analysis, presentation of data to their peers, and ranged from 181-186° while the other four values documentation of their experiences. The following is a ranged from 175-176°. The range of observed values paraphrased summary of their reflections. between separate observers in our group does not appear to be random. This outcome could have been The double star STFA 46 AB were two stars with caused by ineffective tightening of the astrometric magnitudes of 6.0 and 6.2. This made it easy at times eyepiece in the draw tube. The eyepiece would have to see the stars separation and drift as they were been skewed in the same direction each time leading clearly visible. Being able to work together as a group, to consistently incorrect position angles. The four val- having a positive attitude, helping explain to the next ues between 175-176° were taken concurrently so all person where to look in the eyepiece and how to control of the observers could have been looking at the secon- the alt-az hand pad seemed to be extremely helpful. dary star. Other things that made data collection smoother were A similar pattern of observed position angles with the handouts the lead professor gave us. These were respect to literature values is noted for STF 1843 AC. handouts on how to calibrate the eyepiece, using data- The ten recorded position angles ranged from 53-63° bases for double star research, and data collection. with a mean of 58°. The literature value was 64°. The Also, working with college professors offered a rare literature values were again rechecked: WDS at 64° experience for high school students, and having college (2007) and TheSkyX at 63° 6 minutes. All but one of students with astronomical experience as team cap- the observed values were less than the literature tains deepened the experience further. The two college value, indicating some source of systematic error. The students in the group taught us how to make observa- misaligned astrometric eyepiece is the most probable tions and calmed fears of not getting the data correct source of error. or done in time. One way they did this was by drawing In order to alleviate this problem in future stud- a diagram of the astrometric eyepiece and explaining ies, several operations are considered essential. First, how to read measurements on it. This really helped us for separation values less than 30 arc seconds, it is because we were not familiar with this equipment. recommended that a 2x-3x Barlow lens be used in conjunction with the astrometric eyepiece so the in- We had a night of unfavorable weather which re- creased magnification will allow a more accurate quired us to do the double star and triple star meas-

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urements back to back the following night without References checking our double star data for errors. The triple star STF 1843 ABC gave us additional challenges. Observing and Measuring Visual Double Stars, R. Both stars were higher in magnitude making it more Argyle, Springer, London 2004. of a challenge to see them. Also, Bootes was setting Burke, M., 1998, Missing Values, Outliers, Robust behind the Observatory very quickly, it was still a bit Statistics, and Non-Parametric Methods, RHM breezy, and the sky had moderate transparency due to Technologies, Ltd., Scientific Data Management, 2 haze. The team knew they had to be attentive and alert (1), 19-24. to finish getting the data. We could have chosen another star system that was higher in the sky and possi- Frey, Thomas, Spring 2008, Journal of Double Star bly easier to see given the conditions we had been Observations, 3(2), 59-65. working with, but we did choose this system to study Hipparcos and Tycho Catalogs, 1997. and came up with some interesting results under pres- sure by a team of novice and experienced observers Mason, B., The Washington Double Star Catalog, that required in depth analysis. 2009, Astronomy Department, U.S. Naval Obser- vatory. Mazeh, T., et.al., 1996, Astrophysical Journal, 477, Acknowledgements L103. The team would like to express their thanks to Tom Smith, and Joseph Carro for reviewing this pa- Ragahavan, D., et.al., 2006, Astrophysical Journal, per and for their excellent suggestions. We would also 646(1), 523-542. like to thank Greg Bothun, director of Pine Mountain SIMBAD database: http://simbad.u-strasbg.fr/simbad/ Observatory, and to Mark Dunaway, Kent Fairfield, Allan Chambers, and Rick Kang for opening the fa- TheSkyX software: http://www.bisque.com/sc cilities and for being on hand to answer questions and Turner, N.H., et.al., 2001, Abstract @Astrophysical assist our needs. Data System, The Astronomical Journal, 121, Thank you goes to Rick Watkins and Thomas 3254. Frey as co-directors this year, and to Russ Genet as workshop advisor. Thanks to The Evergreen State College staff: Dean Allen Olson, and to Peter Robin- son (Director of Lab I, Lab II, and science technician) for all of your support and time given to answer questions. Appreciation also goes out to ShiLu Vanasupa who assisted in prescreening the target double and triple stars for all teams at PMO prior to the workshop.

Chandra Alduenda and Alex Hendrix are students at The Evergreen State College and have participated at the PMO summer workshops and the Oregon Star Party in 2010 and 2011. Navarre Hernandez-Frey is a student at Kentridge High School, Kent, Washington. Gabriela Key is a student at St. Mary’s Academy, Portland, Oregon. Patrick King is a student at Oregon Episcopal School, Portland, Oregon. Rebecca Chamberlain, Member of the Faculty, The Evergreen State College, teaches interdisciplinary programs that link sciences, humanities, and the arts. She has taught Earth and Sky Sciences for Antioch Uni- versity's Teacher Education Program, and has worked as the lead Science Interpreter in the Starlab Planetarium at the Pacific Science Center. Thomas Frey is a Professor Emeri- tus of Chemistry at California Polytechnic State University. He was a Team Leader at the PMO Workshop 2009, the Principle Investigator of the double star group at the PMO Workshop in 2010, and co-director of the PMO summer research workshop, 2011.

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Comparison of Data on Iota Boötes Using Different Telescope Mounts in 2009 and 2010 by the St. Mary’s School Astronomy Club

Holly Bensel1, Ryan Gasik1, Fred Muller1, Anne Oursler1, Will Oursler1, Emii Pahl1, Eric Pahl1, Nolan Peard1, Dashton Peccia1, Jacob Robino1, Ross Robino1, Monika Ruppe1, Peter Schwartz1, David Scimeca1, Trevor Thorndike1

St. Mary’s School Medford, Oregon

Abstract: Teachers and students from St. Mary’s School in Medford, Oregon attended the 2009 and 2010 Astronomy Research Workshop at Pine Mountain Observatory in Oregon. They compared the accuracy of their double star observations on an Alt-Az and equatorial telescope mount using the star Iota Bootes. Our results showed no significant difference between the use of either mount.

Introduction A double star is defined by two different cate- gories: binary systems, in which stars are close enough relative to each other in space to have significant gravitational interactions; and optical double stars, which are gravitationally unrelated stars that only appear to be near each other when viewed from Earth. Data collection over several centuries is necessary to determine in which category a double star belongs. This is accomplished through detailed measurements of separation and position angles that are used to determine the status of the system. We present our visual measurements of the double star Iota Bootes as part of our process toward becoming accurate and efficient double star observers. This project is a continuation of initial stud- Figure 1: St. Mary’s Astronomy Club 2010: Back Row left to ies carried out at the Pine Mountain Observatory right: Emma Dauterman, Corey Cattanach, Chris Ladue, Cody Holliday, Trenton Hoyle, Will Oursler, Conor Keating, Nolan Summer Science Research Workshop in 2009. At Peard, Ryan Gasik, Guo Zihan, Qiu Hongxiang, Jacob Robino, that time a small group from the St. Mary’s Astron- Conrad Stout, Peter Schwartz, Ross Robino, Tom Hilton. Front omy Club (Figure 1) worked towards and accom- Row left to right: Holly Bensel, Monika Ruppe, Dashton Peccia, Emii Pahl. Not Pictured: Fred Muller, Anne Oursler, Dave Sci- plished the composition of a paper on the neglected meca, Trevor Thorndike double star ARY 52 (Frey, et. al., 2009). It was the

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Comparison of Data on Iota Boötes Using Different Telescope Mounts in 2009 and 2010 ...

goal of this group to master techniques in the observation of double stars and to use this information in their further research with their astronomy club which is based on the campus of St. Mary’s School in Medford, Oregon. Afterwards, sixteen assorted high school and middle school students learned how to take data on double stars and how to write a proper research paper. Data was collected on the campus track which is located at [42.3o N latitude, 122.8o W longitude] at an elevation of 1380 feet above sea level. Viewing conditions on the track are relatively bright but low magnitude double stars are still clearly visible in our telescope. After several weeks of data collection on known double stars, and comparing our results with those published in the Washington Double Star Cata- log (Mason, 2009), the club was ready to study a Figure 2: Setting up the telescope at St. Mary’s School, 2009. “neglected” double star. A neglected double star is one Left to right: Monika Ruppe, Fred Muller, Will Oursler, Misha that has not been observed extensively or recently. Zavalzowski, Ryan Randall, Ryan Gasik. Unfortunately, fall and winter in Southern Oregon can be unpredictable. The fall and winter seasons of accurate as those made while the telescope was in the the 2009/2010 academic year were cloudy and rainy. more familiar Alt-Az configuration. The club was unable to take the telescope out until July and August of 2010. In July the telescope mount Equipment was converted from Alt-Az to equatorial using a The St. Mary’s Astronomy Club uses a Meade 10” wedge. It was discovered that with the new mount LX200 Schmidt-Cassegrain telescope which was gen- came new challenges. These challenges included unfa- erously donated by Fred Muller in 2007 (Figure 2). In miliarity with the new mount and hence difficulty in both the 2009 and 2010 observing seasons a 12.5mm aligning the telescope. Celestron Micro Guide astrometric eyepiece was used. Before measurements could be obtained on the The telescope mount was converted from an Alt-Az neglected stars, the group needed to be certain they configuration to an equatorial configuration in the could obtain results of an equal or better quality to July of 2010, leading to a few changes in the method those achieved when the mount was in Alt-Az con- of operation. These changes in operation are specific figuration. Therefore, data was collected on Iota to the position angle and will be described in detail Bootes, one of the double stars which the club had later in the paper. gathered data on in the fall of 2009 at St. Mary’s Calibration School. This new data was taken during the 2010 Pine Mountain Observatory Summer Science Re- The first step in observing double stars is to search Workshop. Pine Mountain Observatory is lo- calibrate the linear scale on the astrometric cated at [43.8o N latitude, 120.9o W longitude] at an eyepiece in units of arc seconds per division. Argyle elevation of 6500 feet above sea level near Bend, Ore- (p. 152) suggests using a reference star of medium gon. The dry, desert-like climate and dark skies make brightness at a declination between 60o and 75o to for excellent viewing. avoid timing errors. If the star is below 60o then the field drift is too slow, and above 75o is too fast to al- Hypothesis low accurate timing. Therefore, the club used Mizar, It was hypothesized that the switch from the Alt- at 59o 52.379’ declination, because it was easily visi- Az telescope mount to the equatorial mount would not ble and close to the recommended range. The time result in any significant differences in the data as component is measured by placing the calibration star long as the telescope operators were experienced with on the eastern edge of the linear scale and allowing it the new setup. However, the researchers were not to drift in right ascension to the other side of the experienced with the setup, consequently it was scale. This drift is timed using a stopwatch to the speculated that the measurements might not be as nearest .01 seconds. To reduce random errors, many

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trials were made by different individuals from the 7.5) were bright enough to allow effective observa- club. The average of all these trials was used to deter- tions. It is located at a right ascension of 14h 16.5’, mine the scale constant (Z) for the telescope eyepiece and a declination of 51o 19.25’. The Washington Dou- system. ble Star Catalog cited the separation and position angle as 38.7 arc seconds and 34o respectively (WDS, TRS15.0411 cos( ) 2009). Our results are for measurements of Iota Z = ave D Bootes are shown in Table 2. The separation between the primary and secondary star is found by aligning the two with the linear where Z is the scale constant (in arc seconds per divi- scale and estimating the distance between them to sion), Tave is the average drift time, 15.0411 is the the nearest 0.1 division. The pair of stars are moved arc seconds per second of the Earth’s rotation at the across the scale periodically to reduce bias between celestial equator, cos(RS) is the cosine of the reference measurements. The average of these measurements is star’s declination, and D is the number of division on multiplied by the scale constant to obtain the separa- the linear scale. This is 60 divisions for our Celestron tion in arc seconds (Argyle, p. 152). eyepiece. The students took twelve separation measure- The reference star used in the calculation, Mizar, ments in 2009 at St. Mary’s School and made nine had an average drift time of 47.64 s (standard devia- separation measurements during the Pine Mountain tion of 0.31s. and mean error of 0.10 s). This resulted Workshop in 2010. As mentioned earlier, the differ- in a scale constant of 6.85 arc seconds per division. ence in operation between 2009 and 2010 was in the We used this value during the 2010 Pine Mountain acquisition of the position angle. In the Alt-Az ar- Workshop. We were confident of this value since we rangement the students used a method described by repeatedly obtained similar results on multiple nights Frey (2008) and taught to St. Mary’s participants at at St. Mary’s School during the fall of 2009. The scale the 2009 Pine Mountain Workshop (Frey, et al., constant data are summarized in Table 1. 2009). The astrometric eyepiece is rotated until the stars are aligned with the linear scale. The scope is Separation and Position Angle Meas- manually moved using the right ascension and the urement of Iota Bootes declination control knobs to allow the primary star to Iota Bootes was chosen for this project because it drift through the mid mark on the linear scale and is an extensively studied double star with known move outward to a circular protractor scale, where separation and position angle measurements. Hazy the position angle is observed and recorded to the sky conditions in Medford, OR made this star system nearest 0.5o (Argyle, p. 153). In the equatorial con- ideal because the magnitudes of the two stars (4.9, figuration the primary star was placed at the center

Table 1: Data used in the Excel spreadsheet calculation of the scale constant for a 10” LX200 Schmidt- Cassegrain telescope.

Besselian AveDriftTime Std Mean Scale Eyepiece Star Declination #Obs Epoch (Sec) Dev Error Constant Celestron Astro Mizar 2011.57 54 55’ 51” 10 47.64 0.31 0.1 6.85 Reticule

Table 2: Comparison of Separation and Position Angles of Iota Bootes in 2009 and 2010.

Besselian Lit. Obs. Lit. % Type of Double Star Identifier #Obs. SD/ME Epoch Epoch Sep. Sep. Difference Mount Iota Bootes 14162+5122 2004.09 2009 11 0.304/0.092 35.6 34 6.32 Alt-Az (2009) Iota Bootes 14162+5122 2010.06 2009 9 0.870/0.290 37.1 34 2.37 Equatorial (2010) Besselian Lit. Obs. Lit. % Type of Double Star Identifier #Obs SD/ME Epoch Epoch PA PA Difference Mount Iota Bootes 14162+5122 2004.09 2009 15 1.24/0.32 32 38.7 3.63 Alt-Az (2009) Iota Bootes 14162+5122 2010.06 2009 8 2.44/0.70 32 38.7 3.93 Equatorial (2010)

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of the linear scale using the telescope hand controller Acknowledgements keypad and the eyepiece rotated so that the double The St. Mary’s Astronomy Club would like to star aligned with the linear scale. The Right Ascen- thank Russell Genet, Research Scholar in Residence sion motor was then deactivated. The position angle at California Polytechnic State University, for provid- was determined by observing which degree marking ing the workshop that gave us the experience to learn the primary star crossed on the outer protractor scale about double stars. We would also like to thank Tho- and rounding to the nearest 0.5o. Once the star mas Frey for his guidance and support. We want to crossed the protractor scale the motor was turned on thank the Pine Mountain Observatory for making the and the procedure was repeated with the reticule ro- observatory available for workshops. We thank Fred tated 180o approximately every five trials to reduce Muller for donating the telescope and Dave Scimeca bias. for donating technical expertise his time. Acknowl- Conclusions and New Directions edgement is also directed to the faculty and staff at St. Mary’s School for providing facilities and financial The students’ separation and position angle meas- support to the astronomy club. urements when using the Alt-Az telescope mount were similar to their measurements using the equato- References rial mount. The percent error of the position angle Observing and Measuring Visual Double Stars, Ar- was 3.63% in 2009 and 3.93% in 2010. In 2010 there gyle, Robert., Springer, London, 2004. were four outliers due to inexperienced operators. The percent error of the separation distance was Frey, Thomas G., October 2008, Journal of Double 6.32% in 2009 and 2.37% in 2010. The error was less Star Observations, 3(2), p. 59-65. the result of the mount and more the result of opera- Frey, Thomas G., October 2009, Journal of Double tor error and lack of familiarity with the telescope Star Observations, 5(4), p. 212-216. configuration. The club will need to practice with the equatorial mount so that the alignment and other Mason, Brian. The Washington Double Star Catalog. procedures yield more precision and accuracy. July 2009. Astronomy Department, U.S. Naval In addition to improving our operational skills Observatory. http://ad.usno.navy.mil/wds/ over the summer of 2011, the club plans to add pho- wds.html. tometry of double and triple star systems to our skill set.

Holly Bensel is a science teacher at St. Mary’s School in Medford, Oregon. Fred Muller is a retired science teacher and a substitute teacher at St. Mary’s School. Dave Scimeca is a retired technician from Ames Research Center. Ryan Gasik, Anne Oursler, Will Oursler, Emii Pahl, Eric Pahl, Nolan Peard, Dashton Peccia, Jacob Robino, Ross Robino, Monika Ruppe, Peter Schwartz, and Trevor Thorndike are current and former high school students at St. Mary’s School in Medford, Oregon.

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351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

Rafael Caballero

Agrupación Astronómica Hubble Martos, Jaén, Spain

Email: [email protected]

Abstract: This paper presents 351 previously uncataloged pairs with separation under 100 arcseconds and proper motion over 70 milliseconds of arc/year. These pairs are the result of an extensive study that started with 96,205 candidate pairs from the Sloan Digital Survey (SDSS). Different criteria explained in the paper are applied to increase the probability of a physical bound between the components.

the the WDS (Washington Double Star Catalog, Ma- Introduction son et al., 2003). Dhital et al. (2010) takes a different This paper presents 351 new common proper mo- approach, trying to minimize the number of false tion pairs (CPMP’s) obtained from the seventh data positives. The more than 1000 pairs obtained have release of the Sloan Digital Sky Survey (SDSS-DR7, been included in the WDS. Abazajian et al. 2009). The characteristics of the The purpose of this paper is similar: starting pairs are: with a set of candidates from the SDSS, we use several filters, either based on statistical or on physical • Separation between 6 and 100 arcseconds properties, with the goal of eliminating chance align- • Proper motion over 70 milliseconds of arc/ ments of stars. We also have checked the results, year verifying that all the pairs presented appear with noticeable movement in the Aladin plates (Bonnarel The idea of using the SDSS for obtaining new et al., 2000). The CPMP’s data and images obtained pairs is not new. A first list of wide double stars in can be downloaded from http://gpd.sip.ucm.es/rafa/ this catalog was proposed by Sesar, Ivezić, and astro/sdss Jurić (2008). By using the DR6 version of the catalog Initial set of candidate pairs the authors considered stars with proper motion over In previous projects we had obtained the initial 15 milliseconds of arc/year, matched components to set of stars using VizieR (available from http:// within 5 milliseconds of arc/year, and identified vizier.u-strasbg.fr/viz-bin/VizieR). However, this pro- 22,000 total candidates with excellent completeness, ject involves a much larger number of stars, and a but with a one third of them expected to be false timeout error was obtained in VizieR when trying to positives. Also, Longhitano and Binggeli (2010), pre- obtain the initial set of stars. Fortunately, the SDSS sented a statistical research based on this catalog. project includes a Catalog Archive Server query tool However, due to the large number of false positives, (available from http://casjobs.sdss.org/CasJobs/ ). In the results of these papers could not be included in particular this tool allows the user to define directly

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351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

their SQL queries and save the result in the server. Finally, in the second criterion the 0.05 value is We started downloading those stars with r magnitude replaced by 0.07, which implies requiring that all the <19, and with proper motion over 50 milliseconds of pairs must have proper motion over 70 milliseconds of arc/year. This yielded a set of 572,649 stars. Then the arc/year. first set of candidates was obtained by finding all the After applying these more restrictive criteria, only pairs with separation under 100 seconds. This pro- 5690 pairs were left duced an initial set of candidates with 96,205 pairs. 3. Relating colors Filters According to Sesar et al. (2008) the inequality:

Next we explain the different filters that we have (r1 - r2) [( g - i )1 - ( g - i )2] > 0; used to reduce the possibility of chance alignments, that is, to increase the possibility of obtaining physi- where the subscript 1 is assigned to the brighter com- cally attached pairs. ponent, must be satisfied. This condition requires that the component with bluer g - i color be brighter 1. Elimination of cataloged pairs in the r band. This filter reduced the number of candi- The WDS catalog was compared with our set of dates to about 4723 pairs. candidates, looking for already discovered pairs. This allowed eliminating about 200 pairs, most of them 4. Reduced Proper Motion criterion with identifier SLW (from the Sloan Digital Sky Sur- The Reduced Proper Motion (RPM) discriminator vey SLoWPoKES Catalog, see Dhital et al. 2010). proposed by Salim & Gould (2003) requires both the V and J magnitudes for each component. In particular, 2. Modified Halbwachs’ criteria the V magnitude was difficult to obtain for the fainter Halbwachs (1986) defined the following three cri- stars. In the cases where it was possible (about 60% teria for detecting physically attached pairs: of the sample), the criterion was applied. This elimi- (1) (µ1 - µ2) 2 < -2 (e12 + e22) ln (0.05) nated about 20 pairs of the candidate set.

(2) |µ1|, |µ2| ≥ 0.05 5. Checking the photographic plates (3) ρ / |µ1|, ρ /|µ2| < 1000 yr This step is necessary because all the catalogs where µ1, µ2 are the two proper motion vectors in include many errors, usually introduced during the arcseconds/year, ei is the mean error of the projec- catalog generation. Therefore, every pair was checked tions on the coordinate axes of µi, and ρ is the angu- for two stars with noticeable motion and roughly the lar separation of the two stars. The first condition same astrometry data in the expected position. This checks if the hypothesis µ1 = µ2 is admissible with a was done applying the assoc and the RGB utilities 95% confidence considering the given errors e1 and e2. included in Aladin. The surveys employed were the The second condition fixes a value of 50 milliseconds POSS I and POSS II plates corresponding to the Palo- of arc/year as the minimum required for proper mo- mar Observatory Sky Surveys (Reid et al., 1991), and tion pairs. The third condition relates the separation the SERC for the parts of the sky not covered by and the proper motion. POSS II. The result of this last step was that only 351 In order to improve these criteria, the author pro- of the 4700 candidates can be seen in the plates as poses some improvements. The first one is to apply CPMPs. Table 1 includes the data of the new pairs. criterion (1) to both axes (RA and DEC) separately in The complete set of RGB compositions can be seen at: order to reject different proper motion vectors. Also, it http://gpd.sip.ucm.es/rafa/astro/sdss/images/ has been found that the original criteria allow some photo.html pairs with large proper motion differences. Therefore, Conclusions an additional criterion is introduced: delete all the pairs verifying that the proper motion difference in The great numbers of surveys that can be ac- any axis is: cessed online provide an important resource for ama- teurs. In particular, they allow us to find new possible Greater than 10 milliseconds of arc/year, • binaries. However, in order to increase the quality of and, the results, different criteria must be employed in • Greater than the 10% of the minimum of the order to eliminate as many line-of-sight pairs as pos- two values sible. Although we cannot ensure that the 351 CPMP’s proposed in this paper are true binaries, the

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 60

351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

number of criteria applied indicate that they are at Dhital, S.; West, A. A.; Stassun, K. G.; Bochanski, J. least good candidates that deserve a deeper study. J., 2010, “Sloan Low-mass Wide Pairs of Kine- matically Equivalent Stars (SLoWPoKES): A Acknowledgements Catalog of Very Wide, Low-mass Pairs” The As- The author thanks John Greaves for suggestions tronomical Journal, Volume 139, Issue 6, pp. 2566 and helpful comments. This research makes use of -2586. the ALADIN Interactive Sky Atlas and of the VizieR database of astronomical catalogs, all maintained at Halbwachs, J.L., 1986, “Common proper motion stars the Centre de Données Astronomiques, Strasbourg, in the AGK3”. Bull. Inf. Centre Donnees Stel- France, and of the data products from the Two Micron laires, 30, p.129. All Sky Survey, which is a joint project of the Univer- Longhitano, M.; and Binggeli, B.; 2010, “The Widest sity of Massachusetts and the Infrared Processing Binary Stars: A Statistical Approach”, Astronomi- and Analysis Center / California Institute of Technol- cal Society of the Pacific, 435, 67. ogy, funded by the National Aeronautics and Space Administration and the National Science Foundation. Mason, B. D.; Wycoff, G.; Hartkopf, W. I., 2003, “The This work partially supported by the Spanish projects Washington Double Star Catalog”, http:// TIN2008-06622-C03-01, S2009TIC-1465, and UCM- ad.usno.navy.mil/wds/ BSCH-GR58/08-910502. Reid, I. N.; Brewer, C.; Brucato, R. J.; References McKinley, W. R.; Maury, A.; Mendenhall, D.; Mould, J. R.; Mueller, J.; Neugebauer, G.; Phin- Abazajian, K. N.; Adelman-McCarthy, J, K.; Agüeros, ney, J.; and 3 coauthors, 1991, “The second Palo- M, A.; Allam, S. S.; Allende Prieto, C.; An, D.; mar Sky Survey”, Astronomical Society of the Pa- Anderson, K. S. J.; Anderson, S. F.; Annis, J.; cific 103, 661-674. Bahcall, Neta A.; and 194 coauthors, 2009, “The Salim, S.; Gould, A., 2003, “Improved Astrometry and Seventh Data Release of the Sloan Digital Sky Photometry for the Luyten Catalog. II. Faint Survey”, The Astrophysical Journal Supplement, Stars and the Revised Catalog”, The Astrophysi- 182- 2, id. 543-558. cal Journal, 582, 1011-1031. Bonnarel, F.; Fernique, P.; Bienaymé, O.; Egret, D.; Sesar, B.; Ivezić, Ž.; Jurić, M.; 2008, “Candidate Disk Genova, F.; Louys, M.; Ochsenbein, F.; Wide Binaries in the Sloan Digital Sky Survey”, Wenger, M.; Bartlett, J. G.; 2000, “The ALADIN Astrophysical Journal, 689, 1244. interactive sky atlas. A reference tool for identifi- cation of astronomical sources”, Astronomy and Astrophysics Supplement, 143, p.33-40.

Table begins on next page.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 61

351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

RA DEC (2000) Mags Angle Separation DATE PM-A PM-B 00 16 26.98 -11 55 51.2 15.21 18.96 59.89 10.80 1994.952 +102.0 +2.0 +107.0 +5.0

00 17 05.88 -12 04 44.6 16.58 17.01 117.47 80.26 1994.952 +88.0 -14.0 +88.0 -9.0

00 21 16.56 -09 55 03.9 15.68 18.95 4.75 21.03 2000.737 +83.0 +3.0 +84.0 +3.0

00 46 36.93 -22 41 52.2 13.09 14.39 290.99 36.08 1994.985 +55.0 -56.0 +55.0 -56.0

01 02 18.55 +00 25 39.1 15.08 18.09 0.37 63.90 2002.679 +85.0 -28.0 +85.0 -32.0

01 11 50.94 +26 46 16.8 14.17 17.67 234.99 20.77 2004.653 +38.0 -68.0 +34.0 -69.0

01 12 50.16 +20 06 50.2 14.50 14.85 334.12 20.91 2004.707 +76.0 -45.0 +78.0 -46.0

01 19 29.98 -00 02 29.5 14.46 16.05 119.94 18.58 2001.890 -10.0 -149.0 -8.0 -149.0

01 19 33.88 +24 49 56.1 16.52 16.79 266.24 64.53 2004.707 -12.0 -72.0 -9.0 -71.0

02 17 23.13 +70 45 37.4 16.70 18.34 148.42 31.64 2005.841 -59.0 +73.0 -61.0 +71.0

02 20 13.79 +05 34 36.2 16.78 17.35 97.92 28.51 2005.781 +15.0 -71.0 +14.0 -69.0

02 32 43.91 +74 08 54.7 18.31 18.51 160.89 14.76 2005.841 +211.0 -57.0 +207.0 -56.0

02 33 01.17 +01 05 38.8 15.63 16.09 344.56 29.13 2001.890 +134.0 -47.0 +147.0 -44.0

02 46 54.25 -02 18 59.1 13.48 19.53 307.29 23.72 1996.242 +73.0 -11.0 +73.0 -14.0

03 04 29.29 +00 03 20.4 15.43 16.27 186.09 84.41 2002.679 +80.0 -28.0 +82.0 -27.0

03 04 50.47 +37 56 10.2 18.49 18.95 129.20 8.01 1994.172 +130.0 -60.0 +122.0 -56.0

03 05 46.37 +01 45 40.7 16.39 17.54 333.30 28.47 2004.954 -17.0 -131.0 -12.0 -130.0

03 06 35.88 +00 25 47.5 15.48 16.43 335.84 30.03 2002.679 -38.0 -69.0 -40.0 -66.0

03 15 26.76 +02 27 31 13.95 19.04 58.54 21.48 1995.051 +36.0 -67.0 +36.0 -68.0

03 17 45.82 +00 59 36.2 18.00 19.16 97.04 11.91 2002.679 -51.0 -53.0 -56.0 -55.0

03 26 36.25 +05 10 11.7 15.95 16.36 84.78 41.13 2004.953 +73.0 -4.0 +79.0 +1.0

03 48 20.76 +11 03 14.4 17.98 18.07 308.30 54.01 1995.051 -11.0 -74.0 -8.0 -71.0

03 52 48.82 +00 19 28.6 15.96 18.19 102.53 16.58 2001.890 -42.0 -106.0 -42.0 -100.0

04 23 16.87 +17 00 41.6 16.18 17.64 335.36 28.31 1995.051 +85.0 -11.0 +86.0 -6.0

04 30 06.37 +09 02 27.8 15.57 16.23 251.98 16.11 1995.076 -33.0 -69.0 -31.0 -71.0

04 48 04.93 +59 40 35.2 16.40 16.40 358.24 22.09 2004.790 +86.0 -71.0 +83.0 -69.0

05 06 12.74 +61 31 46 14.76 18.97 78.60 43.05 2004.951 +55.0 -59.0 +58.0 -65.0

05 30 46.74 -00 34 04.3 15.84 18.01 283.66 15.11 1996.124 -84.0 -128.0 -83.0 -131.0

05 31 09.56 +63 20 40.6 15.53 17.99 71.93 27.13 2004.951 +44.0 -112.0 +48.0 -115.0

05 39 45.69 +19 04 19.6 15.01 19.03 248.03 19.61 1995.076 +20.0 -72.0 +25.0 -77.0

06 07 52.65 +35 20 30.5 14.40 18.00 23.02 11.93 1995.065 +44.0 -80.0 +46.0 -80.0

06 13 55.36 +05 14 22.6 13.99 17.72 46.35 67.24 1996.125 +7.0 -78.0 +13.0 -76.0

06 40 27.16 +64 15 14.3 14.91 16.91 25.07 14.38 2004.951 +11.0 -140.0 +11.0 -137.0

07 27 50.79 +42 28 19 15.99 17.83 172.80 32.09 2003.886 +53.0 -146.0 +52.0 -145.0

07 28 20.78 +31 00 11.7 15.06 17.83 296.12 9.40 1995.128 +25.0 -143.0 +20.0 -141.0 07 35 40.38 +27 49 25.3 15.53 16.77 102.42 17.56 2001.966 -83.0 -52.0 -81.0 -52.0

Table continued on next page.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 62

351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

RA DEC (2000) Mags Angle Separation DATE PM-A PM-B 07 47 23.50 +24 38 23.7 18.10 18.82 312.08 35.78 2000.740 +136.0 -68.0 +137.0 -70.0

07 58 50.08 +46 26 41.6 15.57 17.53 326.97 12.99 2000.315 -88.0 +7.0 -88.0 +6.0

08 00 30.27 +51 31 54.6 13.86 17.67 164.76 17.57 2003.886 -9.0 -75.0 -12.0 -70.0

08 01 29.38 +19 40 39.5 13.83 18.96 131.35 57.41 2004.129 +29.0 -81.0 +28.0 -80.0

08 04 49.03 +19 20 00.9 12.40 16.12 301.03 39.20 2004.209 -31.0 -72.0 -31.0 -69.0

08 05 19.03 +11 06 44.6 14.74 17.75 296.37 14.96 2005.830 +36.0 -83.0 +39.0 -82.0

08 05 32.28 +31 24 51.6 12.94 18.66 120.92 25.07 2001.890 -38.0 -98.0 -37.0 -102.0

08 09 32.51 +54 06 26.6 16.23 18.97 180.52 64.75 2003.913 +20.0 -69.0 +16.0 -69.0

08 14 12.84 +14 08 49.6 15.69 18.33 36.07 21.97 2004.970 -66.0 -69.0 -62.0 -72.0

08 14 43.65 +46 50 36.5 15.84 18.62 8.70 15.97 2000.740 -48.0 -73.0 -46.0 -71.0

08 19 47.96 +42 27 24.9 14.74 18.68 9.23 29.90 2000.979 -8.0 -94.0 -1.0 -94.0

08 20 02.34 +48 23 19.8 15.21 16.25 291.54 45.19 2000.258 -108.0 -78.0 -106.0 -77.0

08 20 59.44 +17 02 48.7 18.27 19.54 283.35 30.62 2004.946 +55.0 -76.0 +57.0 -82.0

08 22 00.54 +82 16 30.5 15.21 16.61 26.13 28.62 1994.235 -58.0 -47.0 -59.0 -53.0

08 22 31.76 +37 27 47.6 13.41 19.18 50.77 32.97 2001.967 -48.0 -130.0 -41.0 -129.0

08 25 06.62 +12 13 47.5 17.85 18.15 124.45 51.19 2005.194 -51.0 -55.0 -54.0 -62.0

08 25 52.69 +29 25 16.8 18.87 19.35 288.26 16.30 2002.950 -39.0 -86.0 -31.0 -83.0

08 29 25.73 +30 33 45.5 13.49 16.60 312.89 16.91 2002.950 -59.0 -58.0 -54.0 -60.0

08 30 00.61 +28 14 21.5 15.06 18.29 307.04 37.21 2002.999 -104.0 -49.0 -110.0 -57.0

08 30 55.74 +32 59 21.1 17.15 18.84 157.46 65.15 2002.106 -32.0 -66.0 -41.0 -63.0

08 31 04.59 +15 08 59.6 15.57 17.06 284.76 47.17 2005.047 +52.0 -54.0 +53.0 -54.0

08 32 49.93 +11 56 13.5 14.60 19.27 250.65 18.58 2005.860 +4.0 -73.0 +11.0 -72.0

08 33 12.08 +26 45 51.7 14.80 18.84 207.83 43.02 2003.078 -84.0 -30.0 -90.0 -37.0

08 33 51.86 +24 26 12.8 17.64 19.29 69.67 42.67 2003.971 -61.0 +121.0 -63.0 +117.0

08 33 54.63 +12 19 48.3 13.64 14.62 295.73 38.68 2001.145 +59.0 -46.0 +58.0 -46.0

08 34 48.64 +22 57 52 15.32 18.31 300.68 27.69 2004.211 -54.0 -89.0 -63.0 -93.0

08 37 33.67 +24 41 31.6 14.51 18.36 132.78 99.64 2004.130 -158.0 -121.0 -154.0 -128.0

08 39 42.71 +18 01 25.4 15.31 16.30 206.05 28.22 2001.146 -86.0 +9.0 -83.0 +10.0

08 43 34.72 +63 08 26.8 15.03 17.78 199.41 19.56 2003.914 -46.0 -60.0 -45.0 -61.0

08 43 54.05 +58 28 47.1 16.08 16.96 347.24 23.29 2003.810 -26.0 -72.0 -28.0 -75.0

08 46 24.02 +24 02 12.4 16.80 17.32 110.30 22.20 2004.212 -79.0 -71.0 -78.0 -73.0

08 50 53.57 +57 57 32.2 13.95 16.29 282.79 45.72 2003.812 -57.0 -73.0 -62.0 -69.0

08 51 35.02 +35 31 45.7 14.62 17.81 191.08 18.74 2002.106 -42.0 -91.0 -39.0 -90.0

08 52 31.52 +54 44 01.9 14.11 19.14 152.45 29.75 2001.213 +6.0 -118.0 +14.0 -117.0

08 56 16.24 +13 32 26.7 14.03 15.39 255.86 99.30 1994.172 -35.0 +113.0 -38.0 +113.0 09 08 52.09 +25 28 09.1 13.06 18.40 66.65 44.39 2004.288 -58.0 -57.0 -54.0 -63.0

Table continued on next page.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 63

351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

RA DEC (2000) Mags Angle Separation DATE PM-A PM-B 09 10 03.05 +21 32 59.8 15.90 17.92 189.14 24.42 2004.956 -76.0 -19.0 -76.0 -13.0

09 12 13.45 +28 38 06.5 18.52 19.41 295.66 36.81 2004.209 -18.0 -74.0 -18.0 -78.0

09 13 23.70 +47 09 08.4 12.89 19.07 138.47 14.88 2001.290 +44.0 -67.0 +50.0 -73.0

09 17 59.87 +51 38 16 15.18 15.45 184.76 24.41 2001.287 -83.0 -72.0 -77.0 -67.0

09 25 07.78 +63 58 18.1 14.27 16.07 296.17 14.20 2001.457 -61.0 -108.0 -63.0 -105.0

09 26 34.96 +45 47 22.9 13.90 16.99 259.14 13.37 2001.890 +6.0 -70.0 +6.0 -70.0

09 27 54.14 +28 38 21.7 14.66 16.82 115.43 45.78 2004.212 -102.0 -50.0 -105.0 -52.0

09 29 44.91 +24 32 01.8 15.16 15.92 84.89 27.31 2004.367 -26.0 -93.0 -22.0 -95.0

09 29 58.48 +35 51 40.5 14.53 17.91 68.23 11.45 2003.067 -52.0 -47.0 -48.0 -52.0

09 30 07.88 +05 43 01.4 15.35 16.70 203.78 11.13 2002.12 +83.0 -94.0 +85.0 -98.0

09 30 10.14 +39 19 44 14.51 15.46 289.88 15.35 2002.851 -57.0 -52.0 -59.0 -53.0

09 35 18.99 +52 31 37.4 14.95 15.80 194.75 14.30 2001.287 -6.0 -91.0 -9.0 -92.0

09 35 31.66 +15 14 10.6 17.47 17.70 85.45 15.99 2005.356 -120.0 +5.0 -122.0 +1.0

09 35 58.70 +52 41 36.4 12.78 16.81 253.18 16.03 2001.287 -56.0 -68.0 -57.0 -73.0

09 36 35.32 +60 39 24.6 14.08 15.62 173.11 65.63 2000.321 -55.0 -46.0 -55.0 -46.0

09 42 22.52 +64 22 23 13.05 18.39 277.53 14.80 2003.81 -174.0 -61.0 -172.0 -60.0

09 42 41.04 +33 33 38.9 14.75 16.39 242.62 45.59 2003.316 -75.0 -12.0 -73.0 -11.0

09 49 53.28 +50 17 15.2 16.35 16.39 310.57 21.22 2001.888 -86.0 -28.0 -92.0 -24.0

09 51 24.13 +24 55 51.5 16.87 18.57 84.16 21.48 2004.951 +51.0 -56.0 +53.0 -57.0

09 54 23.33 +42 19 45.4 16.27 16.56 229.54 27.21 2002.851 -71.0 +19.0 -73.0 +15.0

09 54 35.54 +26 58 00.1 16.84 17.43 336.50 28.97 2004.367 -26.0 -79.0 -27.0 -77.0

09 55 25.45 +13 42 37.5 16.13 17.68 206.93 57.95 1994.326 +51.0 -56.0 +49.0 -53.0

09 57 03.39 +26 39 04.2 13.69 15.98 101.29 50.57 2004.946 -71.0 -32.0 -68.0 -35.0

10 00 17.81 +68 29 03.4 17.79 18.70 13.34 15.51 2003.914 -47.0 -62.0 -42.0 -66.0

10 02 43.44 +40 09 48.2 15.68 17.57 33.03 29.96 2002.999 -127.0 -24.0 -125.0 -19.0

10 02 50.04 +10 05 39.4 12.46 17.33 314.47 69.96 2002.953 -47.0 -73.0 -46.0 -72.0

10 04 17.82 +47 31 51.7 16.23 18.28 334.91 26.42 2002.035 -79.0 +10.0 -77.0 +5.0

10 06 23.07 +07 12 12.6 16.03 18.91 175.40 18.46 2001.788 +35.0 -67.0 +34.0 -65.0

10 09 38.24 +40 41 14.3 16.76 17.02 203.84 35.29 2002.999 -60.0 -73.0 -64.0 -72.0

10 10 15.24 +47 25 07.6 14.16 15.19 134.42 19.58 2001.970 -19.0 -70.0 -20.0 -71.0

10 10 18.68 +01 07 19.8 16.88 18.21 113.92 8.64 2000.979 -106.0 +35.0 -99.0 +36.0

10 14 01.60 +03 05 50.3 18.26 18.32 277.62 26.50 2000.343 +106.0 -104.0 +104.0 -102.0

10 14 12.19 +31 18 13.3 14.41 18.22 262.37 43.05 2004.291 -81.0 -35.0 -88.0 -34.0

10 14 31.93 +01 53 09.7 15.48 17.21 225.95 21.24 2000.343 -131.0 -50.0 -127.0 -54.0

10 22 08.98 +34 27 02 17.62 17.97 70.55 28.14 2004.212 -65.0 -30.0 -63.0 -31.0 10 23 50.47 +31 52 45.5 15.67 15.96 38.64 39.33 2004.288 -70.0 +7.0 -72.0 +7.0

Table continued on next page.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 64

351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

RA DEC (2000) Mags Angle Separation DATE PM-A PM-B 10 25 20.17 +30 57 42.1 18.23 18.91 112.64 35.09 2004.288 -78.0 -65.0 -83.0 -62.0

10 28 54.79 +33 48 01.7 14.41 16.93 285.76 20.29 2004.083 -42.0 -67.0 -42.0 -65.0

10 29 58.12 +00 43 16.8 11.69 17.81 274.82 30.44 1999.220 +29.0 -88.0 +38.0 -85.0

10 31 03.06 +05 59 39.5 18.74 18.80 32.11 28.27 2002.120 -39.0 -85.0 -32.0 -85.0

10 32 18.86 +27 59 25.9 13.22 15.98 265.67 30.38 2004.957 -71.0 +19.0 -68.0 +19.0

10 37 28.27 +29 31 32.8 13.02 16.45 324.77 43.96 2004.970 -80.0 -59.0 -76.0 -59.0

10 38 41.16 +02 06 38.4 12.80 17.98 303.01 24.75 2000.979 -89.0 +6.0 -90.0 +7.0

10 40 15.25 +36 05 31.6 14.01 17.04 177.18 19.96 2003.316 -24.0 -78.0 -22.0 -72.0

10 40 25.69 +61 53 25.8 13.3 0 17.99 127.72 40.92 2002.120 -82.0 -102.0 -81.0 -110.0

10 45 01.14 +25 37 15.4 15.34 18.46 298.65 9.85 2004.973 -91.0 -33.0 -96.0 -38.0

10 50 04.73 +59 51 50.1 14.23 16.00 113.02 13.52 2000.908 -54.0 -60.0 -51.0 -63.0

10 50 12.05 +32 41 10.2 16.01 18.57 287.82 8.95 2004.291 -75.0 +20.0 -67.0 +23.0

10 50 47.21 +62 04 48.5 18.18 18.31 48.92 19.26 2000.258 -70.0 -13.0 -78.0 -16.0

10 53 06.72 +03 40 17.7 13.49 18.79 129.47 24.33 2001.140 -88.0 +2.0 -85.0 +3.0

10 54 16.19 +00 02 58.8 15.40 16.90 117.27 42.13 1995.541 +104.0 -102.0 +109.0 -103.0

10 59 46.73 +22 42 46.7 18.09 18.36 352.33 25.12 2005.096 +35.0 -98.0 +36.0 -94.0

11 00 05.29 +42 43 18.2 16.53 18.76 322.85 12.03 2003.226 -46.0 -80.0 -47.0 -80.0

11 02 01.89 +23 53 07.9 15.52 16.60 118.95 97.80 2002.350 -146.0 -96.0 -146.0 -92.0

11 02 24.47 +24 35 44.5 14.62 18.62 226.84 63.78 2005.096 -123.0 -5.0 -120.0 -8.0

11 02 47.68 +30 18 45 14.37 17.75 310.00 17.47 2004.362 -95.0 -11.0 -99.0 -7.0

11 07 53.89 +41 54 58.1 12.30 18.60 90.21 60.26 2003.313 -97.0 +3.0 -99.0 +1.0

11 09 51.06 +47 37 08.6 14.12 18.35 301.79 10.49 2002.106 -112.0 -9.0 -114.0 -6.0

11 11 42.91 +06 32 45.8 14.25 18.80 166.13 13.20 2002.120 +34.0 -73.0 +40.0 -80.0

11 11 57.06 +04 58 22.4 15.18 17.77 289.02 24.58 2001.290 -87.0 -55.0 -88.0 -51.0

11 15 22.27 +02 51 32.3 17.04 18.33 186.90 47.77 2000.343 +75.0 -32.0 +67.0 -40.0

11 15 48.96 +32 02 14.4 14.02 18.88 156.89 38.88 2004.362 +5.0 -84.0 +8.0 -87.0

11 16 44.03 +07 14 06.5 14.41 17.64 246.97 22.98 2003.248 +44.0 -66.0 +49.0 -66.0

11 18 21.04 +29 13 08 17.74 18.53 237.84 16.48 2004.951 -106.0 -28.0 -100.0 -25.0

11 20 12.17 +25 28 21.5 15.92 16.57 116.30 21.60 2005.096 -19.0 -113.0 -19.0 -110.0

11 21 45.09 +02 16 58 14.41 18.88 98.67 10.60 2000.979 +9.0 -131.0 +12.0 -141.0

11 21 58.65 +54 44 48.7 15.68 15.95 163.5 30.97 2002.999 -77.0 -44.0 -74.0 -46.0

11 26 44.77 +25 03 16.3 16.32 17.68 355.39 12.35 2003.076 -80.0 -38.0 -78.0 -39.0

11 27 24.67 +04 35 06.4 12.67 15.84 259.48 64.66 2001.290 -74.0 +3.0 -74.0 +2.0

11 29 59.10 +24 47 06.6 15.67 16.89 75.64 19.82 2005.096 -76.0 -4.0 -75.0 -3.0

11 31 42.15 -08 44 51.5 16.51 18.55 183.90 25.57 1994.266 -90.0 +7.0 -96.0 +7.0 11 33 30.32 +33 08 29.5 13.62 16.79 211.24 56.84 2004.367 -110.0 -9.0 -107.0 -13.0

Table continued on next page.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 65

351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

RA DEC (2000) Mags Angle Separation DATE PM-A PM-B 11 33 59.84 +16 56 46.8 17.11 17.50 328.79 64.55 2005.427 -130.0 -46.0 -124.0 -47.0

11 35 40.32 +04 57 29.7 15.42 19.60 30.53 10.16 2001.290 -239.0 +43.0 -230.0 +34.0

11 37 15.80 +31 56 52.3 15.78 17.41 261.54 26.29 2004.368 -147.0 -17.0 -146.0 -21.0

11 39 30.94 -02 08 16.4 15.25 17.91 128.75 13.26 2000.116 -102.0 +62.0 -99.0 +67.0

11 40 07.53 +37 57 43.2 12.37 16.17 196.41 18.55 2003.087 -91.0 -3.0 -93.0 -8.0

11 43 42.12 +54 57 44.4 15.80 17.58 175.93 29.45 2001.964 -91.0 +24.0 -91.0 +22.0

11 44 08.82 +19 14 20.5 14.87 16.47 212.75 15.15 2005.252 -106.0 -18.0 -105.0 -15.0

11 44 54.22 +14 26 20.9 14.22 18.88 203.08 31.78 2003.076 -93.0 -45.0 -93.0 -41.0

11 45 10.15 +31 50 01.2 14.11 17.54 138.83 29.10 2004.362 -75.0 +49.0 -77.0 +50.0

11 45 17.40 +03 19 25.7 13.76 16.27 316.95 87.84 2000.343 -76.0 -118.0 -75.0 -120.0

11 45 46.44 +17 50 40.2 14.90 16.68 351.08 87.43 2003.180 -122.0 +19.0 -123.0 +15.0

11 46 46.23 -03 33 54.7 13.72 17.48 175.82 61.84 2000.171 -82.0 +24.0 -82.0 +16.0

11 46 57.13 +20 56 18.6 15.20 15.23 261.60 25.31 2005.252 -83.0 -13.0 -80.0 -8.0

11 47 02.29 +35 04 32.2 14.55 17.84 303.54 12.15 2004.283 -71.0 +20.0 -73.0 +19.0

11 48 01.80 +23 56 56.7 14.77 16.71 172.97 52.07 2005.050 -87.0 +9.0 -85.0 +8.0

11 51 47.12 +27 02 36.3 12.85 15.54 212.79 20.67 2004.973 -76.0 -32.0 -82.0 -33.0

11 51 47.28 +17 00 11.6 14.83 17.84 157.01 12.19 2005.416 -79.0 +6.0 -72.0 +7.0

11 53 01.76 +45 12 51.4 15.70 16.98 94.56 30.41 2003.226 -76.0 -43.0 -74.0 -40.0

11 54 13.29 +20 23 20.2 14.90 16.37 74.72 14.75 2003.322 -73.0 +7.0 -70.0 +7.0

11 58 09.14 +05 42 54.2 12.41 15.44 81.81 69.59 2003.407 -73.0 +25.0 -70.0 +25.0

11 59 48.15 -03 15 16.9 14.68 17.41 353.62 24.73 2000.171 -70.0 +5.0 -72.0 +6.0

12 00 21.27 +09 09 32.1 14.98 18.76 157.50 9.94 2002.194 -102.0 0.0 -103.0 -6.0

12 00 47.62 +26 11 44 14.18 14.37 250.78 21.88 2003.472 -67.0 -22.0 -72.0 -24.0

12 01 27.52 +21 27 28.3 12.15 18.85 294.85 21.92 2005.189 +15.0 -131.0 +17.0 -134.0

12 03 01.61 +11 05 11.5 12.52 15.64 144.79 17.52 2002.944 -57.0 -90.0 -56.0 -98.0

12 03 10.93 +49 48 50.9 17.40 18.91 164.54 19.30 2003.809 -98.0 -39.0 -98.0 -37.0

12 04 21.77 +63 00 48.1 15.85 18.36 186.40 91.47 2000.908 -103.0 -43.0 -102.0 -42.0

12 04 41.04 +09 16 56.3 15.18 17.91 251.99 81.39 2002.194 -80.0 -35.0 -71.0 -40.0

12 06 02.12 +12 18 18.1 13.66 16.49 269.49 38.12 2003.245 -11.0 -184.0 -5.0 -182.0

12 06 41.64 +66 20 57.7 12.64 17.68 56.39 48.39 2000.264 -74.0 -14.0 -73.0 -16.0

12 09 21.21 +06 39 15.9 15.25 17.99 74.43 8.55 2003.248 -89.0 +23.0 -80.0 +24.0

12 10 32.69 +33 16 13.3 15.75 16.74 303.81 13.75 2004.316 -89.0 -12.0 -94.0 -14.0

12 12 36.34 +23 47 20.6 14.78 15.47 173.10 27.82 2005.252 -83.0 -68.0 -83.0 -67.0

12 17 58.15 +27 51 27.8 12.73 17.61 330.59 37.02 2005.050 -82.0 +20.0 -82.0 +17.0

12 21 48.21 +04 32 26.8 15.99 17.46 243.50 74.40 2005.435 +39.0 -85.0 +36.0 -80.0 12 22 44.44 +03 24 40.1 14.44 17.96 338.86 39.74 2000.343 -125.0 +62.0 -120.0 +54.0

Table continued on next page.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 66

351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

RA DEC (2000) Mags Angle Separation DATE PM-A PM-B 12 23 16.53 +66 45 38.8 15.61 17.99 313.05 33.43 2000.264 -83.0 -51.0 -83.0 -49.0

12 26 33.24 -02 10 05.8 13.92 14.18 336.25 12.74 2000.116 +53.0 -114.0 +49.0 -105.0

12 30 50.45 +54 08 00.4 16.69 17.73 139.74 8.83 2002.248 -85.0 +1.0 -89.0 -6.0

12 31 43.49 +63 54 30.9 12.75 16.77 122.94 17.86 2001.072 -110.0 -6.0 -108.0 -7.0

12 34 59.74 +20 26 26.5 16.53 18.85 191.54 32.19 2005.356 -75.0 +26.0 -77.0 +28.0

12 35 14.00 +53 36 03.5 14.07 16.98 76.15 79.90 2002.036 -77.0 -65.0 -83.0 -57.0

12 35 32.66 +17 52 16.6 16.13 18.12 325.87 22.91 2005.430 +77.0 -57.0 +75.0 -59.0

12 36 13.33 +14 57 16.5 15.80 17.74 14.23 80.54 2003.076 -158.0 -107.0 -157.0 -107.0

12 39 34.60 +18 17 17.4 16.57 18.39 282.08 44.59 2005.416 -56.0 -75.0 -58.0 -81.0

12 40 08.25 +37 21 46.1 14.33 17.19 76.61 33.03 2004.206 +114.0 -191.0 +118.0 -191.0

12 40 43.12 +46 26 55.4 17.00 18.93 257.23 11.51 2003.191 -26.0 -77.0 -31.0 -79.0

12 41 12.37 +50 38 18.7 15.54 17.41 138.10 13.05 2002.106 -72.0 +30.0 -74.0 +29.0

12 42 38.32 +61 21 24.4 18.31 19.00 147.56 6.35 2004.288 -73.0 -24.0 -65.0 -27.0

12 43 04.91 +10 10 02.5 12.41 16.11 27.18 35.12 2003.319 -119.0 -58.0 -129.0 -54.0

12 44 58.89 +42 48 13.2 15.59 18.00 70.37 22.60 2004.291 -103.0 -46.0 -102.0 -45.0

12 47 19.20 +02 29 39.4 14.81 16.99 83.76 18.93 2000.343 -104.0 -29.0 -104.0 -22.0

12 48 33.42 +04 08 36.7 13.17 17.03 319.90 40.62 2001.290 -86.0 -1.0 -86.0 -3.0

12 53 28.40 +36 12 30.4 14.38 14.99 278.19 14.98 2004.291 -79.0 +2.0 -77.0 +5.0

12 55 33.51 +26 27 25.8 14.65 17.52 177.98 21.99 2004.973 -76.0 -40.0 -74.0 -39.0

12 55 46.88 +05 00 23 16.01 18.94 26.92 9.98 2001.290 -74.0 -20.0 -81.0 -19.0

12 56 39.38 +31 02 40.8 16.68 18.36 192.87 35.39 2004.362 +51.0 -85.0 +50.0 -83.0

12 59 54.49 +36 20 06.2 14.93 17.67 168.60 13.21 2004.130 -16.0 -105.0 -14.0 -104.0

13 00 54.03 +09 39 39.9 15.39 16.22 171.01 24.38 2003.319 +36.0 -124.0 +34.0 -121.0

13 02 51.78 +32 37 55.4 11.86 18.25 96.21 56.30 2004.362 -69.0 +14.0 -70.0 +12.0

13 03 27.85 +42 50 09.9 16.10 18.94 170.00 43.17 2003.313 -59.0 +95.0 -54.0 +91.0

13 05 11.27 +06 54 54.6 15.76 17.58 153.05 7.51 2003.248 -77.0 -12.0 -71.0 -21.0

13 07 34.85 -02 45 07.6 15.71 18.91 278.63 44.45 2000.171 +8.0 -76.0 +10.0 -85.0

13 08 15.79 +08 12 46.8 17.36 18.16 329.73 11.82 2003.248 -17.0 -85.0 -18.0 -88.0

13 09 03.20 +35 54 40 12.75 16.49 196.01 93.60 2004.207 -79.0 -89.0 -75.0 -89.0

13 10 21.34 +32 52 58.6 14.37 17.19 359.92 66.43 2004.362 -175.0 +1.0 -178.0 0.0

13 10 39.43 +07 14 20.9 15.63 15.99 301.59 23.34 2003.248 -77.0 -58.0 -81.0 -62.0

13 10 53.48 +54 39 25.6 14.47 17.90 344.27 8.50 2002.287 -70.0 -9.0 -73.0 -3.0

13 11 21.11 +58 56 13.4 14.23 16.54 234.86 34.08 2002.120 -73.0 -9.0 -70.0 -5.0

13 13 39.49 +59 14 25.4 13.80 18.85 289.88 16.15 2002.120 -70.0 -27.0 -68.0 -29.0

13 14 26.82 +17 32 09.2 16.29 18.50 341.15 19.96 2004.393 -40.0 -58.0 -41.0 -58.0 13 14 46.90 +25 44 26.3 16.52 18.03 110.07 8.56 2004.973 -97.0 0.0 -89.0 -2.0

Table continued on next page.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 67

351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

RA DEC (2000) Mags Angle Separation DATE PM-A PM-B 13 16 14.32 +15 56 28.3 13.21 15.77 273.37 19.37 2005.416 -73.0 -17.0 -72.0 -13.0

13 16 37.70 +12 43 37.8 15.23 18.19 141.02 62.17 2003.223 -87.0 -4.0 -86.0 +3.0

13 17 45.23 +00 32 52.1 14.36 15.92 24.60 35.81 2004.447 -105.0 -34.0 -103.0 -35.0

13 19 46.52 +53 57 51.9 14.52 16.06 170.95 16.04 2002.287 -34.0 -74.0 -32.0 -74.0

13 21 56.02 +23 04 43.7 14.18 16.04 304.59 30.88 2005.252 -75.0 -2.0 -73.0 -1.0

13 22 15.77 +05 31 17.7 15.05 17.70 236.54 46.92 2001.214 +26.0 -137.0 +25.0 -137.0

13 23 58.43 +10 29 23 16.00 16.56 169.77 21.35 2003.322 -86.0 -101.0 -80.0 -92.0

13 25 18.32 +15 14 17.4 15.88 16.88 142.31 21.91 2004.075 +56.0 -44.0 +54.0 -47.0

13 25 36.98 +43 44 37.6 16.46 16.83 165.70 9.69 2003.226 -5.0 -77.0 -4.0 -81.0

13 26 59.36 +02 29 41.5 15.89 18.55 176.52 15.89 2000.343 -151.0 -40.0 -159.0 -40.0

13 33 04.16 +38 13 07.6 15.70 18.34 233.12 9.11 2003.316 -45.0 -67.0 -49.0 -64.0

13 36 02.47 +18 45 51.6 14.74 17.53 54.78 32.60 2004.710 -133.0 +28.0 -132.0 +26.0

13 40 10.74 +14 30 41.6 14.36 18.77 88.03 63.59 2004.075 -31.0 -64.0 -31.0 -63.0

13 46 30.50 +15 22 22 15.67 18.75 234.78 11.99 2005.359 -67.0 -26.0 -69.0 -30.0

13 49 53.35 +28 54 57.2 14.57 15.44 358.16 53.99 2004.713 +4.0 -94.0 +6.0 -99.0

13 53 00.71 +04 32 56 15.13 18.57 277.18 23.77 2004.729 -61.0 -75.0 -65.0 -78.0

13 54 03.88 +16 31 10.9 15.80 17.17 8.77 36.23 2005.359 -72.0 -29.0 -71.0 -27.0

13 54 51.71 +51 28 15.6 15.09 18.09 333.53 10.32 2002.248 -67.0 -44.0 -68.0 -41.0

13 57 48.38 +24 47 36.3 16.89 17.34 147.51 36.46 2004.447 -76.0 +24.0 -77.0 +24.0

13 58 34.98 -08 09 59.5 14.75 15.10 143.70 13.46 1994.637 -81.0 +63.0 -72.0 +60.0

13 59 15.99 +13 34 03.1 15.28 15.69 206.47 22.44 2004.075 -77.0 -15.0 -75.0 -10.0

14 03 41.15 +14 40 55.7 15.40 18.38 358.61 54.76 2005.364 -64.0 +46.0 -60.0 +48.0

14 05 54.78 +19 29 40.2 17.68 18.89 17.15 7.47 2005.195 -60.0 +38.0 -65.0 +41.0

14 08 23.52 +11 40 03 18.24 18.95 248.65 36.79 2003.314 +58.0 -91.0 +58.0 -97.0

14 09 37.83 +13 49 15.4 15.17 17.75 235.33 19.16 2003.409 -81.0 +4.0 -82.0 -4.0

14 10 48.81 -03 05 21.1 14.16 15.47 315.00 18.08 2001.394 -93.0 -65.0 -90.0 -59.0

14 12 32.44 +07 17 46.1 14.49 17.28 355.59 11.82 2003.319 +65.0 -104.0 +69.0 -100.0

14 13 28.70 +23 31 12.7 14.11 17.27 299.23 11.37 2004.450 -72.0 -52.0 -70.0 -52.0

14 15 34.71 +48 06 42.1 14.49 16.66 163.61 40.35 2003.324 -77.0 -12.0 -79.0 -9.0

14 16 41.14 +32 32 28.1 14.13 17.35 291.05 10.42 2004.288 -27.0 +99.0 -31.0 +105.0

14 17 57.35 +07 25 35.1 16.07 18.11 148.32 18.20 2001.457 -76.0 +41.0 -81.0 +39.0

14 18 34.18 +17 20 00.2 14.46 18.44 295.97 56.58 2005.356 +113.0 -17.0 +120.0 -20.0

14 19 46.72 -02 30 22 18.64 18.76 109.57 35.15 2001.454 -81.0 -40.0 -76.0 -39.0

14 19 56.10 +16 33 37.2 15.13 16.10 267.34 63.24 2005.353 -83.0 +23.0 -87.0 +21.0

14 21 53.99 +00 18 08.3 14.81 15.67 266.75 32.57 1999.221 -77.0 -8.0 -73.0 -7.0 14 23 39.16 +04 07 29.7 13.92 16.06 300.98 16.20 2001.214 +36.0 -111.0 +30.0 -117.0

Table continued on next page.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 68

351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

RA DEC (2000) Mags Angle Separation DATE PM-A PM-B 14 24 35.95 +18 04 13.5 16.44 18.70 224.83 33.32 2005.354 -157.0 -72.0 -155.0 -73.0

14 26 56.81 +55 39 27.8 17.55 17.57 159.60 14.53 2002.437 -83.0 +22.0 -84.0 +25.0

14 28 13.25 +10 13 20.9 16.63 17.93 205.43 19.54 2003.245 -80.0 -27.0 -79.0 -23.0

14 30 56.06 +13 01 12.3 17.88 18.95 294.19 11.80 2003.472 +34.0 -80.0 +37.0 -75.0

14 32 27.35 +48 05 28.2 15.04 18.81 239.14 85.27 2003.246 -91.0 +81.0 -93.0 +74.0

14 33 58.89 +17 18 54.7 15.53 15.59 41.87 18.48 2005.356 -54.0 +58.0 -54.0 +61.0

14 34 48.15 -01 16 35.6 15.41 16.97 111.73 38.97 2001.394 -184.0 -134.0 -178.0 -132.0

14 35 01.29 +05 12 04 13.19 15.16 83.51 70.05 2003.319 +25.0 -98.0 +26.0 -101.0

14 35 45.91 +04 58 11.3 17.41 17.52 335.38 51.82 2001.214 +31.0 -164.0 +33.0 -168.0

14 35 50.15 +00 42 34.4 16.26 18.02 138.09 49.80 1999.221 +80.0 -88.0 +82.0 -89.0

14 41 23.90 +11 41 10.2 15.58 18.30 257.43 36.51 2003.409 +12.0 -106.0 +17.0 -101.0

14 41 50.04 +15 02 35.1 15.45 18.11 36.10 60.84 2005.362 -9.0 -74.0 -9.0 -74.0

14 42 04.11 +16 53 35.5 16.64 17.44 266.12 32.22 2005.354 -73.0 +11.0 -70.0 +13.0

14 42 47.19 +28 07 20.7 15.14 15.93 184.73 95.82 2004.308 +56.0 -85.0 +57.0 -87.0

14 43 53.39 +48 00 19.1 17.56 18.87 259.16 34.71 2002.350 -62.0 -35.0 -58.0 -41.0

14 46 08.46 +10 59 01.5 12.50 17.10 86.33 20.68 2003.314 +78.0 -143.0 +79.0 -146.0

14 51 12.98 +05 47 55.7 15.03 15.20 12.44 25.55 2003.322 +12.0 -72.0 +12.0 -71.0

14 51 22.03 +08 46 27.2 16.46 16.85 144.84 14.06 2003.322 -118.0 -65.0 -118.0 -64.0

14 52 43.33 +09 20 01.7 13.82 16.35 138.96 15.85 2003.245 -2.0 -105.0 -5.0 -110.0

14 52 45.33 +03 53 42.5 13.19 18.15 174.00 21.50 2001.214 -76.0 -32.0 -75.0 -32.0

14 53 04.87 +53 56 51.3 16.54 18.35 182.49 73.95 2002.437 -26.0 +77.0 -24.0 +78.0

14 54 19.48 +15 54 09.1 14.52 16.68 94.94 10.00 2005.356 -64.0 -61.0 -71.0 -63.0

14 54 31.18 +46 19 55.6 14.70 16.67 35.25 22.81 2005.096 -11.0 -74.0 -9.0 -75.0

14 56 22.86 +33 51 26.1 15.74 18.21 267.44 78.10 2003.475 -144.0 +14.0 -147.0 +19.0

15 00 51.88 +13 14 46.3 15.65 15.88 234.55 19.23 2005.364 +33.0 -156.0 +37.0 -156.0

15 04 15.74 +18 03 26.7 12.48 16.26 183.29 16.21 2005.190 -88.0 -90.0 -88.0 -88.0

15 12 07.12 +29 52 05.8 15.78 15.91 326.88 28.38 2003.480 -82.0 +47.0 -82.0 +40.0

15 12 32.54 +56 29 14.8 14.49 18.01 97.14 15.07 2001.143 -60.0 +40.0 -62.0 +45.0

15 13 21.66 +08 38 20.1 14.96 17.62 152.85 24.78 2003.245 -123.0 -20.0 -124.0 -24.0

15 15 00.25 +20 38 42.8 17.15 18.38 179.06 71.16 2004.450 -10.0 -95.0 -8.0 -89.0

15 15 35.95 +24 30 10.5 18.75 18.94 1.77 41.34 2004.308 +39.0 -83.0 +30.0 -91.0

15 16 01.73 +56 52 22.4 16.23 18.90 339.83 12.05 2000.261 -61.0 +52.0 -59.0 +54.0

15 17 22.82 +09 04 01.3 16.67 18.18 337.80 18.13 2003.314 -90.0 -131.0 -96.0 -134.0

15 20 36.77 +55 08 13.5 14.35 17.75 101.36 17.11 2005.428 -78.0 +82.0 -76.0 +83.0

15 21 34.95 +39 21 58.7 13.72 16.20 40.61 24.93 2002.107 -71.0 +42.0 -71.0 +42.0 15 25 52.08 +12 32 04.8 15.78 17.87 31.91 46.66 2005.362 +3.0 -75.0 +5.0 -76.0

Table continued on next page.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 69

351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

RA DEC (2000) Mags Angle Separation DATE PM-A PM-B 15 29 14.80 +50 26 31 12.86 15.55 204.79 69.70 2002.437 -61.0 +37.0 -63.0 +36.0

15 29 24.12 +17 34 27.8 15.06 18.96 72.40 48.78 2005.356 -95.0 -61.0 -100.0 -55.0

15 34 58.77 +20 35 28.6 17.61 18.88 110.15 7.44 2004.392 -75.0 -34.0 -73.0 -32.0

15 35 20.98 -00 17 51.2 12.09 16.67 219.97 30.08 1999.218 +44.0 -83.0 +46.0 -86.0

15 41 49.74 +26 47 06 15.57 18.25 33.32 13.27 2004.209 -94.0 -4.0 -89.0 -7.0

15 43 19.30 +40 24 09.6 16.17 18.07 315.77 36.80 2005.359 +16.0 -135.0 +17.0 -136.0

15 45 00.78 +19 32 54.8 17.76 18.67 163.53 15.15 2004.392 -77.0 -14.0 -77.0 -21.0

15 45 05.80 +09 23 16.1 17.13 18.81 137.85 53.78 2003.472 -85.0 +4.0 -86.0 +10.0

15 47 05.72 +01 45 47.9 15.00 18.71 286.04 68.35 2000.341 -81.0 -4.0 -75.0 -7.0

15 48 17.61 +37 05 52.3 16.06 17.73 109.26 37.83 2003.407 +19.0 -69.0 +23.0 -73.0

15 50 42.54 +03 01 43.8 15.67 17.58 349.56 24.65 2001.214 -54.0 -92.0 -53.0 -89.0

15 56 09.50 +03 21 48.7 17.80 18.90 142.31 27.76 2001.214 -70.0 -38.0 -73.0 -39.0

16 04 33.30 +09 54 06.2 16.23 18.80 54.04 20.69 2005.362 +25.0 -69.0 +30.0 -70.0

16 07 15.16 +34 57 53.9 14.89 17.22 168.82 67.06 2003.406 -32.0 +83.0 -29.0 +76.0

16 11 42.15 +10 22 26.2 13.12 17.61 91.07 15.16 2005.354 +46.0 -144.0 +51.0 -144.0

16 13 40.56 +39 34 55.1 14.84 18.48 155.01 28.62 2002.353 -69.0 +37.0 -64.0 +30.0

16 14 16.06 +42 15 29.5 15.81 17.99 69.76 24.68 2002.438 -113.0 +70.0 -107.0 +69.0

16 17 09.40 +44 06 47 13.77 16.69 16.17 56.82 2001.375 -35.0 +94.0 -38.0 +93.0

16 27 23.60 +43 36 19.6 15.55 17.98 77.31 16.17 2001.392 -94.0 +51.0 -98.0 +58.0

16 31 49.00 +38 04 52.3 17.07 18.74 249.62 26.00 2002.438 +2.0 +84.0 -1.0 +77.0

16 34 42.40 +22 31 41.4 12.55 18.48 251.85 39.85 2003.330 +5.0 -76.0 +1.0 -71.0

16 42 25.62 +19 08 06 18.82 19.46 333.79 6.38 2003.317 -83.0 +4.0 -84.0 -2.0

16 58 09.95 +26 52 27.1 12.76 17.44 272.40 18.42 2002.353 -83.0 -132.0 -88.0 -134.0

16 58 54.11 +49 42 51 12.92 17.80 53.74 23.18 2004.455 -34.0 +74.0 -33.0 +82.0

17 00 30.24 +33 13 37.1 16.23 17.06 289.30 27.11 2001.392 -46.0 -65.0 -47.0 -66.0

17 16 05.66 +63 06 21.4 13.63 15.86 10.63 31.30 1994.952 -11.0 -81.0 -8.0 -81.0

17 19 45.36 +67 22 58.6 13.19 15.83 219.07 22.95 2001.457 +27.0 -69.0 +28.0 -68.0

17 22 42.87 +71 47 18.1 15.44 18.75 160.08 10.34 2001.720 -13.0 +89.0 -6.0 +87.0

17 27 00.41 +33 06 03.4 14.91 18.58 312.00 39.90 2004.453 +7.0 -71.0 +12.0 -75.0

17 48 35.08 +46 05 51.2 16.23 18.73 34.33 19.83 2001.717 -2.0 +83.0 +1.0 +80.0

17 50 51.17 +49 42 51.9 14.80 15.68 189.73 14.05 1995.122 -35.0 +69.0 -30.0 +66.0

17 57 07.61 +43 03 26.3 15.18 15.34 111.28 35.84 2005.435 -9.0 -79.0 -7.0 -76.0

17 58 34.35 +23 48 21.7 15.60 17.29 265.19 19.81 2004.707 -1.0 -70.0 -8.0 -72.0

19 14 39.93 +37 17 21.5 13.41 16.82 64.86 47.81 2005.444 +28.0 -96.0 +25.0 -103.0

19 16 53.01 +37 14 12.7 14.42 17.42 177.54 28.52 1995.541 -34.0 +93.0 -31.0 +92.0 19 58 24.50 +60 31 54.1 13.69 18.96 246.17 51.55 1994.651 0.0 +96.0 -1.0 +95.0

Table concludes on next page.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 70

351 New Common Proper-Motion Pairs from the Sloan Digital Sky Survey

RA DEC (2000) Mags Angle Separation DATE PM-A PM-B 20 08 28.93 +60 23 54.3 16.19 16.59 355.44 74.14 1994.651 -78.0 -30.0 -81.0 -27.0

20 09 31.23 +31 47 45.6 15.41 17.65 278.99 28.35 2003.317 -29.0 -81.0 -28.0 -83.0

20 33 58.01 +15 42 56.4 14.54 15.53 190.26 50.33 2004.783 +80.0 +41.0 +81.0 +45.0

20 36 44.74 +04 47 07.4 16.44 17.40 234.41 20.45 2005.742 -44.0 -63.0 -51.0 -68.0

20 47 11.39 +00 21 27.6 17.17 18.20 43.31 49.82 2003.324 -6.0 -101.0 -8.0 -95.0

21 00 11.29 +74 32 23.8 13.57 15.76 285.05 48.56 2003.740 -76.0 +24.0 -77.0 +19.0

21 20 56.07 +20 50 15.2 12.37 17.99 327.06 25.51 1994.643 +75.0 +18.0 +75.0 +17.0

21 38 58.41 -00 01 37 14.10 18.89 263.41 80.42 2001.788 +16.0 -91.0 +20.0 -88.0

21 41 56.72 +19 49 09 14.13 14.92 123.47 64.81 2004.712 -64.0 -32.0 -64.0 -34.0

21 43 10.20 +13 49 53.1 17.66 18.47 304.46 13.51 1994.643 -44.0 -66.0 -47.0 -62.0

21 48 59.56 +13 03 32.6 15.47 16.13 236.64 20.77 2000.740 -85.0 -22.0 -86.0 -24.0

21 55 17.40 -00 46 23.4 15.56 15.71 0.52 35.43 2002.777 +61.0 -53.0 +62.0 -52.0

22 03 36.37 +43 58 59.5 14.58 18.79 86.35 13.30 1994.652 +146.0 +49.0 +151.0 +48.0

22 04 48.64 +22 26 28.4 17.41 17.70 40.96 35.49 2004.784 -107.0 -55.0 -109.0 -53.0

22 19 38.34 +22 58 38.1 13.72 17.37 2.57 48.55 2004.712 -69.0 -43.0 -66.0 -49.0

22 20 25.33 +05 19 56.9 16.92 18.56 271.33 31.54 2005.742 -111.0 -118.0 -114.0 -123.0

22 31 44.75 +13 19 23.9 17.02 18.69 298.25 10.54 2000.740 -13.0 -74.0 -14.0 -75.0

22 36 16.06 +21 51 12.4 15.54 17.44 293.61 46.73 2003.738 +106.0 -79.0 +101.0 -77.0

22 36 59.49 +01 07 44.4 16.38 16.72 144.25 23.84 2001.788 +52.0 -47.0 +55.0 -50.0

22 38 58.94 +68 27 39.6 14.54 14.99 37.63 72.57 2003.738 +75.0 -8.0 +76.0 -13.0

22 42 31.14 +12 50 04.9 16.36 16.62 257.73 12.13 2003.738 -33.0 -76.0 -34.0 -73.0

22 52 15.78 +29 03 23.4 16.97 17.84 107.50 19.86 1994.949 -52.0 -52.0 -52.0 -51.0

23 19 26.03 +15 38 17 16.89 18.72 82.08 13.21 2000.740 -29.0 -81.0 -29.0 -79.0

23 19 53.22 -01 05 25.4 16.18 18.75 323.95 23.39 2002.678 -48.0 -78.0 -48.0 -75.0

23 28 43.52 +07 03 10.6 12.79 15.36 74.08 97.65 2004.707 +152.0 -28.0 +147.0 -36.0

23 54 35.23 +24 27 45.6 15.63 16.70 124.05 14.40 2004.712 +87.0 -29.0 +88.0 -27.0 23 59 54.91 -04 12 12.9 16.48 17.09 150.94 77.06 1994.952 -53.0 -96.0 -52.0 -97.0

Table Notes: • Data taken from the SDSS-DR7 survey. • The position angle is in degrees, the separation in arcseconds, and the proper motion in milliseconds of arc/year.

Vol. 8 No. 1 January 1, 2012 Journal of Double Star Observations Page 71

Journal of Double Star Observations The Journal of Double Star Observations (JDSO) January 1, 2012 publishes articles on any and all aspects of astronomy in- Volume 8, Number 1 volving double and binary stars. The JDSO is especially interested in observations made by amateur astronomers. Editors Submitted articles announcing measurements, discover- R. Kent Clark ies, or conclusions about double or binary stars may un- Rod Mollise dergo a peer review. This means that a paper submitted Editorial Board by an amateur astronomer will be reviewed by other ama- Justin Sanders teur astronomers doing similar work. Michael Boleman Not all articles will undergo a peer-review. Articles Advisory Editor that are of more general interest but that have little new Brian D. Mason scientific content such as articles generally describing

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