Vol. 10 No. 3 July 1, 2014 Journal of Double Observations Page Journal of Double Star Observations

July 1, 2014

Inside this issue: Astrometric Measurements of Five Double Report of February 2014 171 Joseph M. Carro

Measuring Binaries with Position-Circle and Filar Micrometer-Screw 174 Robert Korn In Search of DAL 45: Observing on the Edge with a 4 inch Refractor Steven C. Smith and John Nanson 179

Double Star Observations with a 150mm Refractor in 2013 185 Marc Oliver Maiwald

Analysis of Errors in the Measurement of Double Stars Using Imaging and the Reduc Software 193 Tim Napier-Munn and Graeme Jenkinson

A New Double Star in Andromeda 199 T. V. Bryant III

63 New Common Binaries in the LSPM-North Catalog 201 F. M. Rica

Double Star Measures Using the Video Drift Method - IV 214 Richard L. Nugent and Ernest W. Iverson

DSLR Double Star Using an Alt-Az Telescope 223 Thomas G. Frey and David Haworth

Double Star Measurements at the Southern Sky with 50 cm Reflectors and Fast CCD Cameras in 2012 232 Rainer Anton

Discovery of Stellar Duplicity of TYC 1950-02320-1 During Asteroidal Occultation by (141) Lumen 240 Mitsuru Sôma, Tsutomu Hayamizu, M. Ishida; M. Owada; M. Ida; R. Aikawa, A. Hashimoto, T. Horaguchi, K. Kitazaki, S. Uchiyama, S. Uehara, A. Yaeza, Brad Timerson, T. George, W. Morgan, and E. Edens

Announcement: Second Annual Apple Valley Double Star Workshop 245

Announcement: 2014 Lowell Speckle Interferometry Workshop 248

Vol. 10 No. 3 July 1, 2014 Journal of Double Star Observations Page 171

Astrometric Measurements of Five Double Stars Report of February 2014

Joseph M. Carro Cuesta College, San Luis Obispo, California

Abstract: From my residence in Paso Robles, California, the position angles and separations of five double stars were measured. The two objectives of this project were to measure the position angles and separations of the aforementioned stars, and to learn the techniques necessary to con- duct this research.

6.0.0.65; both programs are products of Software Methodology Bisque. Those products were used to operate the tele- The observations were made from my house in scope and camera and to reduce the data. During each Paso Robles, California (located about 35o37'36 "N and o viewing session, six photographs of the reference star 120 41'24" W), using a Celestron telescope model CPC and 10 photographs of the target stars were taken. Not 1100. The telescope is computerized, motorized, and all of the photographs were useful, and the number of was equipped with a CCD camera. The telescope is a useful images is reported for each star. Schmidt-Cassegrain design with an aperture of 279mm. For each viewing session, the date, starting time, The manufacturer gives the focal length at 2,800mm. ending time, temperature, humidity, lunar phase, wind, The CCD camera, a model ST-402, is a product of the and visibility were recorded. This author defines Santa Barbara Instrument Group. "visibility" as the number of stars in the Little Dipper After having aligned the telescope with the Global which can se seen without an instrument, and the inter- Positioning Satellite, a reference star was used to set the val is from 1 to 7 stars. focus, and configure the software. The software consist- A literature search was made for each star, and ed of CCD Soft version 5.00.195 and SKY 6 version those sources for which data was reported are listed.

Position Separation Star Name WDS Number SAO Number BD Number Date # Obs Angle o Arc seconds

HD 218472 in PEG 23079+3128 73021 +30 4881 13 Sept 2013 6 54.6 18.6 WDS 1872 80 10 WDS 2001 14 54.0 18.4 9 - 11:00pm PDT Tem: 20-18oC Hum: 50% ½ moon Wind: calm Vis: 2-3 Both white Other Identifiers ADS 16528 A CSI+30 4881 1 HIC 114224 SAO 73021 AG+31 2387 GC 32222 HIP 114224 SKY# 43909 AGKR 20691 GCRV 14522 IDS 23031+3055 A TD1 29636 BD+30 4881 GSC 02751-00021 2MASS J23075522+3127316 TYC 2751-21-1 CCDM J23079+3128A HD 218472 PPM 88552 WDS J23079+3128A

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A New Double Star in Perseus

Position Separation Star Name WDS Number SAO Number BD Number Date # Obs Angle o Arc seconds ES 1017 in LAC 05278+5009 - +50 1175 27 Sept2013 10 148.6 11.2 WDS 1898 134.0 12.1 WDS 2003 4 148.0 11.2 9: - 11:30pm PDT Tem: 20-15oC Hum: 40% no moon Wind: calm Vis: 3-4 Both white Other Identifiers ADS 15789 A GEN#+0.05402721J LF 4 +55 49 WDS J22152+5530A BD+54 2721 GSC 03986-00232 TYC 3986-232-1 [AC2000b]Trap 895 1

Position Separation Star Name WDS Number SAO Number BD Number Date # Obs Angle o Arc seconds SEI 129 in AUR 05157+3228 - - 29 Dec 2013 6 98.0 8.1 WDS 1895 101 7.5 WDS (Neglected Star) 2001 6 98 8 6 - 9:30pm PST Tem: 10-6oC Hum: 45% no moon Wind: calm Vis: 1-2 Both white Other Identifiers

TYC 2394-951-1 WDS 05157+3228

Position Separation Star Name WDS Number SAO Number BD Number Date # Obs Angle o Arc seconds ES 63 in AUR 05357+4118 40463 +41 1227 31 Dec 2013 9 174.3 8.0 WDS 1894 172 6.4 WDS 1998 174 8 7:30: - 9:30pm PST Tem: 10-5oC Hum: 40% no moon Wind: calm Vis: 1-2 White, blue Other Identifiers ADS 4173 A CSI+41 1227 1 IDS 05287+4114 A TYC 2918-966-1 AG+41 579 ES 63B 2MASS J05354300+4118235 WDS J05357+4118A BD+41 1227 GSC 02918-00966 PPM 48259 CCDM J05357+4118A HD 36720 SAO 40463

Position Separation Star Name WDS Number SAO Number BD Number Date # Obs Angle o Arc seconds ES 891 in AUR 05274+5422 - +54 892 31 Dec 2013 10 72.2 8.1 WDS 1910 1 72 8 7:30 - 9:30pm PST Tem: 10-5oC Hum: 40% no moon Wind: calm Vis: 1-2 White, blue

Other Identifiers ADS 4023 A CCDM J05274+5422A IDS 05192+5417 A TYC 3748-134-1 AG+54 468 CSI+54 892 1 2MASS J05272442+5422161 WDS J05274+5422A BD+54 892 GSC 03748-00134 PPM 29837

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A New Double Star in Perseus

Acknowledgements Grateful appreciation is given to Russell Genet at Cuesta College, for his training on the methodology and use of the CCD camera and software, to Tom Smith for the correct versions of the software, and to Eric Weise for the software updates. This research made use of the SIMBAD database operated at CDS, Strasbourg, France, and the Washing- ton Double Star Catalog maintained by the United States Naval Observatory. References Mason, B., et al., 2012, Washington Double Star Cata- log

For the stars in this report, no data was found in the following references: Hipparcos and Tycho Catalogue, 2011 Hoffleit+, 1991, The Bright , 5th Re- vised Edition, Yale University. Clark, R. ed; Journal of Double Star Observations - all issues McEvoy B., 2011, Herschel 500 Double Star List Muenzler, K., 2003, Eagle Creek Observatory OAG catalog 2003, as reported by the WDS; original list and all 26 supplements

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Measuring Binaries with Position-Circle and Filar Micrometer-Screw

Robert Korn Gailenberg, Germany

Abstract: A method for measuring visual binaries using position-circle and modified micro- scope accessories is described. The measurements of 61 binaries measured in the fall of 2012 are presented and some deviations from values published in the WDS are discussed.

I have done systematic binary observations, i.e. astronomical reticle ocular combined with a microme- measuring separation and position angles, since 2008. ter-screw. In my experience, there are no such items, Before that, this category of targets mostly met my in- new or used, at an affordable price on the market. terest for test purpose only. Instead, I found interesting microscope accessories Now that I am 63 old, my patience while ob- from the Russian manufacturer Lomo. On the Europe- serving has improved, but the sensitivity of my eyes an market there is a micrometer screw device with has decayed. So I changed from visual observing deep- moving reticle plate and ocular available for about sky-objects to the “realm of binaries”. €150. I ordered one and found that this device can be My telescope is quite a veteran; a C8 “orange”, used with an astronomical telescope: Some modifica- manufactured by Celestron in the late '70's. It is an ex- tions and an adapter to fit the different diameters are cellent telescope, able to completely resolve binaries necessary, but this should be no problem for the do-it- down to 0.6" and doing (for a telescope of its class) yourself-experienced amateur. A great advantage of outstanding work on the planets! See Figure 1. The the device: its components can be freely adjusted to- instrument is mounted on an also veteran Vixen AT- gether over wide ranges. LUX based on a massive concrete pier. The ATLUX The focal length of the ocular is about 16mm, thus stepper motors are driven by an FS2-control unit from resulting in a magnification of about 120x. This allows Michael Koch, Germany. This mounting may be measuring separations greater than 10”. I thought judged as oversized for a C8, but gives excellent posi- about using a Barlow lens, but finally decided not to do tioning and a very fine and sensitive handling. so because that would bring one more mechanical com- In choosing the method to measure p.a. and separa- ponent into the system, increasing the risk of instabil- tion I decided for the old-fashioned way: using position ity. For this reason all my observations and measures circle and filar screw micrometer. The reasons: also are done without using a zenith diagonal. First, because my observatory no electricity. Current Furthermore, there is the need to make the fine en- comes only from two modest solar panels; enough to graved markings of the reticle visible against the back- drive my scopes, but no more. For this reason I cannot ground. All my efforts failed to make the markings afford extended computer-sessions necessary for digital “shine” by illumination from the side, so I illuminated imaging and processing the results obtained. Also, the background of the 17´ field of view. A small red working with the Internet can be problematic. LED, its regulated by a variable resistor, Second, I am an old fashioned man and do prefer was placed in front of the measuring device. This observations at the ocular. Purchasing and configuring worked quite well, but limited the observable magni- the equipment was not easy. I was able to buy a second tude to about 9.5. Weaker components are “drowned” -hand Zeiss position circle with a 10 cm diameter in in the red-glowing background. good condition. Far more difficult was the search for an Overall my equipment allows measuring binaries

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Measuring Binaries with Position-Circle and Filar Micrometer-Screw

with a rho over 10" and component magnitudes better than 9.5. Given these limits, I extracted from the WDS lists of objects in the reach of my equipment. One more re- striction I added was to look for binaries, whose rho and/or theta values showed noticeable changes over the times reported. With the equipment described here, I can observe and measure in one 3 hour session - if longer, my eyes get tired - between five and seven pairs. Every pair must "pass" two runs, if the results do not match even more. The results obtained can be evaluated instantly - in my opinion an advantage of the described "handcraft" method. Table 1 gives a list of 61 observation results ob- tained in the Fall of 2012 . Acknowledgements: I want to thank William Hartkopf, USNO for friend- ly and immediate help and information in some uncer- tainties. Gianluca Sordiglioni maintains a useful tool with his website: http://stelledoppie.goaction.it, that gives fast and complex information on double stars. References Mason, Brian. 2012. Washington Double Star Catalog. Astrometry Department, U.S. Naval Observatory. Figure 1. Orange C8 used in this study. The attached mi- http://ad.usno.navy.mil/wds/wds.html crometer and PA circle are also visible just above the eye- piece.

Table 1. Measurements made with equipment described in the text. Angle Name RA Dec Mags 1/2 Sep. (as) Date N Rem. (deg) S 838AD 00h 04.2 62° 17 5.9/8.2 244 197° 2012.805 1 1 STTA256AB 00h 08.0 31° 23 7.1/7.3 110 113.5° 2012.753 1 2 BU 483AC 00h 09.1 40° 51 7/7.7 158.2 269° 2012.753 1 3 BU 484AC 00h 09.7 52° 02 7.6/8.5 81.8 51° 2012.8 1 4 ARY 7AB 00h 10.4 58° 31 7.8/8.3 122.7 1° 2012.8 1 2 ARY 9 00h 11.6 58° 13 7.1/8.6 135.1 81.5° 2012.8 1 5 HJ 1944 00h 13.2 -17° 11 7.7/9 65.3 335° 2012.8 1 6 STF 30AB 00h 27.2 49° 59 7/8.9 14.2 313° 2012.805 1 2 HJ 1968AB 00h 27.7 -16° 25 7.3/8 36.92 232.5° 2012.805 1 7 HJ 323 00h 40.7 -4° 21 6/8.5 62.2 285.5° 2012.8 1 2 H 5 82AB 00h 47.4 51° 06 8/8.4 56 75.5° 2012.808 1 2 STTA 9AB 00h 49.9 30° 27 7.8/8.8 120.9 243.5° 2012.761 1 8 STTA 11AB C 01h 07.2 38° 39 7.6/8.8 60.5 163.3° 2012.761 1 9 HJ 2052 01h 31.6 -19° 01 6.9/7.5 80.5 114° 2012.805 1 2 STF 142AB 01h 39.9 13° 15 8.9/9.2 21.3 65° 2012.805 1 2 KPR 1AC 01h 44.3 9° 29 7.9/8.4 189.8 285° 2012.805 1 2 Table continues on next page.

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Measuring Binaries with Position-Circle and Filar Micrometer-Screw

Table 1 (continued). Measurements made with equipment described in the text.

Angle Name RA Dec Mags 1/2 Sep. (as) Date N Rem. (deg)

STFA 4AB 01h 56.2 37° 15 5.8/6 207.1 298 2012.808 1 10

ARN 90AB 01h 56.8 38° 02 9/9.2 36.9 194.5 2012.808 1 11 STTA 24AB 02h 12.9 57° 12 7.1/8.8 91.1 333 2012.808 1 12 H 6 1AC 02h 19.3 -2° 59 6.7/9.3 124 69.5 2012.816 1 13 BUP 30AC 02h 22.8 41° 24 5.8/7.4 302.2 9.5 2012.816 1 2 WAL 20AC 03h 02.3 41° 24 8/8.9 96.5 211 2012.816 1 2 ENG 11 03h 07.7 36° 37 7.5/9.2 132.5 260 2012.816 1 14 STFA 6 03h 09.2 7° 28 7.7/7.8 80.9 164 2012.816 1 2 SHJ 227AB 16h 21.9 19° 09 3.8/8.8 42.7 228 2012.704 1 2 STT 356AB 18h 33.2 40° 10 7.3/9.2 28 301.3 2012.619 1 15 H 6 50AC 18h 49.7 -5° 55 6.2/8.2 111.3 170.3 2012.614 1 2 HJ 5505 18h 57.7 9° 42 9.4/9.4 14.8 123.8 2012.619 1 16

STF2424AB 18h 59.1 13° 38 5.3/9.3 20.5 301.3 2012.619 1 17

STF2461AD 19h 07.4 32° 30 5.3/9 137.8 291.3 2012.619 1 18 STTA181AB 19h 20.1 26° 39 7.4/7.5 63.8 0.5 2012.622 1 19

HJ 2866AB 19h 23.4 -18° 00 8.6/8.7 23.1 51.5 2012.655 1 20

ARY 19AB 19h 33.3 26° 29 8.9/9.4 13.3 2012.622 1 21

HJ 599AC 19h 40.7 -16° 18 5.4/7.7 45.3 40.3 2012.655 1 22

STF2594 19h 54.6 -8° 14 5.7/6.4 36.7 170 2012.614 1 2

STT 592AC 20h 04.1 7° 04 5.9/6.9 215.1 334 2012.655 1 23

STF2637AC 20h 09.9 20° 55 6.6/7.5 92 221.3 2012.685 1 24

STF2637BC 20h 09.9 20° 55 7.5/8.9 95.1 215 2012.685 1 25

S 735 20h 11.3 -00° 08 7.1/8 55.3 211 2012.685 1 2

ARN 50AC 20h 22.9 27° 08 8.3/8.9 84 330.8 2012.685 1 26

STF2690 20h 31.2 11° 16 7.1/7.4 16.9 255 2012.685 1 27

STF2703AB 20h 36.8 14° 44 8.4/8.5 25.3 291.8 2012.704 1 28

STF2703AC 20h 36.8 14° 44 8.4/8.8 76.2 234.5 2012.704 1 29

STF2703BC 20h 36.8 14° 44 8.5/8.8 66.2 215 2012.704 1 30

S 788 21h 23.8 -06° 35 7.7/8.3 57.3 94 2012.704 1 31

STF2822AD 21h 44.1 28° 45 4.8/6.9 196.5 44.3 2012.712 1 32

BU 696AE 22h 04.5 15° 51 8/10 120 3 2012.704 1 33

HN 56AC 22h 14.3 -21° 04 5.6/8.9 209.8 44.8 2012.712 1 34

ARN 24AC 22h 25.8 -20° 14 6.7/8 129.4 92.3 2012.712 1 35

Table continues on next page.

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Measuring Binaries with Position-Circle and Filar Micrometer-Screw

Table 1 (conclusion). Measurements made with equipment described in the text.

Angle Name RA Dec Mags 1/2 Sep. (as) Date N Rem. (deg)

ARN 24AC 22h 25.8 -20° 14 6.7/8 127.7 89.5 2012.718 1 35

HJ 975 22h 55.7 36° 21 5.7/9.2 53.8 244.5 2012.704 1 36 S 826AC 23h 14.1 -08° 55 7.6/9.1 82 132 2012.704 1 37 STTA246AB 23h 28.0 23° 35 8/8.9 80.9 123 2012.704 1 38 STFA 60AB 23h 28.0 23° 35 7.3/7.5 231.1 208.5 2012.712 1 39 WEB 10AB 23h 38.6 44° 41 8.3/8.8 128 304 2012.721 1 40 ENG 88AaF 23h 43.5 58° 05 7.2/9 277.4 197 2012.712 1 41 STF3041AB 23h 47.9 17° 03 8.4/9 57 358.5 2012.721 1 42 STF3041AC 23h 47.9 17° 03 8.4/9.2 60.7 358.5 2012.721 1 42 STF3044 23h 53.0 11° 55 7.3/7.9 20 283.2 2012.721 1 2 STTA251AB 23h 53.6 51° 31 6.9/9.1 48 209.5 2012.721 1 43 HO 205AD 23h 54.1 39° 17 6.7/9.4 122.7 215.5 2012.721 1 44 ARY 33 23h 59.2 50° 32 7.3/8.1 99.6 140 2012.721 1 2

Remarks: quite consistent with 123" reported. 1. Measures reported from 1991; theta increased 1°, 14. Theta increased 2°. rho unchanged. rho decreased 2" . 15. Theta decreased 1°; rho decreased 2". Consistent 2. Consistent with reported measures. with trend reported. 3. Theta 2°, rho increased 2" . Consistent with trend 16. Theta decreased 1°, consistent with trend report- reported. ed. rho unchanged. 4. Theta is more than 8°, rho less than 2" compared 17. Theta increased 1.5°. Consistent with trend report- with WDS reports. My measured theta is quite ed. consistent with values reported till 2002. 18. Theta somewhat decreased, rho increased 2". 5. WDS reports theta of 125°. Measured theta of Both consistent with trend reported. 135° is near to formerly measured values between 19. Theta no change, rho 2" increased. Consistent 136° and 138°. with trend reported. 6. Theta quite consistent, rho 2" under reported WDS 20. Theta 1.5° under the reported measure. rho 1" value. November 2008 I measured theta 336° and under the reported measure. Both results against rho 67.6". the reported trend. 7. Theta 1.5° under value to expect. rho with an in- 21. Theta consistent with trend reported. No rho crease of 1.2"; that is consistent with trend report- measured due to clouds rolling in. ed. 22. Theta 1.5° under the reported value. Rho con- 8. Theta consistent, rho increased 7" – consistent sistent with reported trend. with trend reported. 23. Theta increased 1°, rho increased 1". Both con- 9. With respect to the last values reported for 1999 sistent with reported trend. theta and rho are unchanged. 24. Theta decreased 1°. rho increased 2". Both con- 10. Theta 1° decreased. rho 7" increased, both con- sistent with reported trend. sistent with trend reported. 25. Theta 1° under reported value; rho quite con- 11. Theta 2.5° increased against the only reported sistent with the trend. measure, rho unchanged. 26. Theta decreases 1°, rho decreases 1". Both con- 12. Theta unchanged, rho increased for 2", both con- sistent with reported trend. sistent with trend reported. 27. Theta unchanged, rho increased 1". Rho con- 13. Mira. Theta increased 1.5° to latest value, rho sistent with reported trend, theta not.

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28. Theta increased 2°. Rho no change. Theta con- 37. Noticeable increase in theta 3° and rho 6". Both sistent with reported trend, rho not. consistent with trend reported. 29. Theta consistent; rho 1" under reported value. 38. Theta increased 2°, rho 1". Both results against 30. Theta 1° under reported value, but in the trend. reported trend. Rho consistent. 39. Theta 1.5° decreased; rho 3" decreased. Last val- 31. Theta increased 1°, rho 2.5". Both consistent with ue with reported trend. trend reported. 40. Theta unchanged; rho increased 2". Thats with 32. Theta no change, rho decreased 1.5". Rho con- trend reported. But only one run measured. sistent with trend reported. 41. Theta slightly increased; rho noticeable increase 33. Theta of 3° not consistent with 316° reported in for 5". Both consistent with reported trend. WDS for 2010. But in good consistence with val- 42. Both A and B show unchanged theta with respect ues obtained before. Rho quite consistent. to C. Both rho have decreased by ~ 4" with re- 34. Theta and rho over reported values and not con- spect to C. sistent. 43. Theta increased by 2.5°, rho increased 1". Results 35. The rho reported here gives a value 5" higher than with trends reported. last WDS value. A repeated observation gave 44. Theta no change, rho increased by 5". An increase quite the same result. Last value in WDS maybe of rho is with the trend, but 5" in 10 years appear erroneous? not to be very probable. Theta consistent with re- 36. Theta no change, rho increased 2". Theta value ported trend. against, rho with trend reported.

The author is a retired lawyer. For 10 years he has enjoyed his astronomical passion in a quiet place somewhat apart from civilization in the Bavarian mountains, where he lives and observes in his log-cabin home at 3300 ft above sea level.

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In Search of DAL 45: Observing on the Edge with a 4 Inch Refractor

Steven C. Smith Castle Rock, Colorado [email protected]

John Nanson Star Splitters Double Star Blog Manzanita, Oregon

Abstract: We discuss our effort to observe and measure DAL 45, a faint component of the Delta Cephei system first measured in 2008 by James Daley.

Over the course of the last and a half my inter- I wasn’t too surprised that in my initial exposures, est (S. Smith) in double stars has been the recording of with the exception of F, several of the fainter compan- photographic images of these captivating systems. As a ions (B D & E) weren’t captured as my ISO settings member of the Double Star Imaging Group on Yahoo and exposure times weren’t set with 14 magnitude stars (http://groups.yahoo.com/neo/groups/double_star_imaging) I in mind. In the case of a multiple system with a great have met and collaborated with others interested in cre- variation in separations and magnitudes, as is the case ating a visual record of double star systems through of Delta Cephei, some trial and error is usually in- photography and sketching. volved to find the right combination of exposure & ISO This particular adventure began in November 2013 to capture all of the components in a single exposure. when I began to photograph the well known and color- My typical imaging train consists of an Olympus E- ful double star Delta Cephei (STFA 58) first catalogued PL1 micro four-thirds format camera shooting through in 1800 by Giuseppe Piazzi. It easily lived up to its bill- a Sky-Watcher 100mm f9 ED refractor, all mounted on ing as a premier visual double and I was able to record a Celestron AVX GoTo Mount. The camera has a 17.3 the blue and gold A-C pair which shares the field of x 13mm Live MOS sensor (4032 x 3024 pixels - 12 view with the triple system H IV 31 located just 6 arc- MP) which equates to a 4.3 um square pixel size. The minutes to the west. It wasn’t until I began processing camera wasn’t chosen as being particularly suitable for the image and checking the WDS data on the system astro-imaging but was simply what I had on hand and that I became aware that Delta Cephei has 4 additional has served me well, producing some very nice images. & very faint companions ranging between 13 to 14 In theory my 4” refractor has a resolution of 1.2 arc magnitude. The information on this multiple system -sec (the Rayleigh Limit) and a limiting visual magni- (from the Stelle Doppie website) is reproduced in Fig- tude of approximately 12. From past experience I ure 1. knew that at prime focus with photographic exposures

NAME CST SAO COORD_2000 DISCOV# COMP FIRST LAST OBS PA SEP MAG1 MAG2 D_MAG Del Cep Cep 34508 22292+5825 BU 702 AB 1878 2012 10 282 21.80 4.21 13.00 8.79 del Cep Cep 34508 22292+5825 STFA 58 AC 1800 2012 87 191 40.60 4.21 6.11 1.90 Cep 22292+5825 DAL 45 AD 1999 2008 3 38 108.50 4.20 13.90 9.70 Cep 22292+5825 FOX9037 AF 1921 2012 4 49 37.40 4.21 13.50 9.29 Cep 22292+5825 DAL 45 DE 2008 2008 1 23 1.40 13.90 14.00 0.10 Figure 1: WDS Data on Delta Cephei as presented in Stelle Doppie

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In Search of DAL 45: Observing on the Edge with a 4 Inch Refractor

Figure 2: (Left) Delta Cephei and nearby triple H IV 31 - (Right) Components of Delta Cephei

up to one minute my setup was capable of capturing the two of us we began to run down the particulars of stars down to about the 14th magnitude. At prime focus DAL 45. the system gives very good resolution, on the order of As can be surmised from its name DAL 45 was the 1.0 arc-sec per pixel based on star-drift timing across 45th double star discovery of James Daley, a prolific the field of view but resolving separations below 4 arc- observer and measurer of double stars with 51 double sec are problematic depending greatly on the relative star discoveries currently to his name. Daley is also brightness of the components. I knew that the search accomplished in astronomical photometry and provided for the faint components, particularly DAL 45, would magnitude measurements for both A-D & D-E which be pushing the capabilities of my scope & camera to along with his astrometric measures were published in their limits. the July 2009 issue of the Journal of Double Star Ob- I resolved to re-visit Delta-Cephei at the first op- servations (JDSO). Daley used a 8” medial (folded) portunity and this came several nights later. I took sev- refractor to make his measurements and noted that D eral 60 sec exposures at various ISO settings and a cur- was a “new component” and DE is a “neat close pair sory review though the viewfinder of the camera for a CCD”. showed that several of the faint components were The WDS database actually contains two entries showing up. When processing, everything looked for AD that predate Daley’s 2008 measures. The first promising – the 13th magnitude B component was was in 1999, the result of the 2 Micron All-Sky Survey peeking through the glare of the 4th magnitude primary (2Mass) which mapped and measured stellar and ex- just 22” away, and 13.5 magnitude F at twice that dis- tended objects at near-infrared wavelengths. The sec- tance was plainly visible, confirming that the limiting ond referenced measurement of AD was in 2003 and magnitude of my system was above the tabulated val- again appears to have been the result of another Sky ues of the stars I was looking for. But components D Survey, this time taking the UCAC4 catalog and & E, the stars that make up the 13.9 magnitude subsys- matching with it all the double stars in the Washington tem of DAL 45, were buried in the noise. It appeared Double Star Catalog to obtain astrometry and photome- faintly on only one of the five frames (see Figure 2) try measurements. The results were published in the and much fainter than expected especially when com- “Double Stars in the USNO CCD Astrographic Cata- pared to F, supposedly only 0.4 magnitude brighter. log” by Hartkopf., Mason, et al. I sent the photo off to John Nanson, author of the Since both AD and the DE pair were given the Star-Splitters Double-Star Blog, who is also a contribu- DAL 45 designation along with the fact that Daley tor to the Imaging Group, for his opinion and between noted that “D is a new component” it can be inferred

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In Search of DAL 45: Observing on the Edge with a 4 Inch Refractor

that the previous two measures were added to the data- Sky Atlas website to measure the Sky Survey photo, base subsequent to Daley’s measures and what ap- which produced a position angle of 40.9 degrees and a peared to be a single star (D) was not associated with separation of 110”. I used AutoCAD on the photo in Delta Cephei prior to 2008. Figure 2, which resulted in a position angle of 37.8 de- Searches of the SIMBAD & ALADIN databases grees and a separation of 108.5” (see Figure 4), which produced sky survey photos, one of which is repro- were in good agreement with the WDS values and con- duced below in Figure 3, which show DAL 45 shining vinced us that the object in my photos was in fact DAL rather prominently in a field of stars reaching down 45. past magnitude 18 and seemed to belie the difficulty I Two of my photos were sharp enough to show was having trying to capture it in my photos - it ap- some hint of elongation rather than just a single faint pears noticeably brighter and nearly equal in magnitude star and were subjected to further processing. At prime to F in comparison to its much dimmer appearance in focus the image of DE occupied an area of only about 4 my photo (Figure 2). x 6 pixels. In an effort to enhance the images which During 8 separate observing sessions spread over have a native image density of 314 pixels per inch, they two months, 43 photos were taken of the Delta Cephei were re-sampled in Adobe Photoshop using the Bicubic system. An object appearing to be in the correct loca- function up to 2512 pixels/inch; an 8 fold increase, re- tion to be DAL 45 appeared in only 8 of them, but it sulting in an image scale of about 0.13 arc-sec/pixel. was enough to remove all doubt that the object in the One image stood out in that after the processing the image was real and not sensor noise or some photo- object resembled a pair of stars in a figure-8 or graphic artifact. “Kissing” orientation at what appeared to be near the Because of the unexpected faintness, John and I tabulated PA and separation values. I am sure the faint measured the A-D distance and PA for the object. John and nearly equal magnitudes of the two stars along used the measuring tools available on the ALADIN with good seeing were working in my favor to get this

Figure 3: DSS Survey Photo of Deta Cephei - DAL 45 centered in crosshairs

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refute Daley’s measurements, but this could be an in- teresting project for someone with an imaging system with better resolution to check out. This enhanced image was imported into AUTO- CAD and measured (results shown in Figure 5), which was further assurance that this was indeed DAL 45. Due to the significant under-sampling of the image (a deviation of even a fraction of a pixel in the re- sampling process or setting the origin of the measure- ment points could significantly change the results) the Position Angle and Separation measures cannot be con- sidered as definitive but do show what detail can be teased out of digital images using relatively simple im- aging devices and software. As final confirmation I wanted to measure the combined magnitude of the DE pair since it was the fainter-than-expected image that prompted all of my previous efforts. For this I turned to the software pack- age, IRIS, a freeware astro-imaging software package developed by Christian Buil that provides functions for astronomical image manipulations and photometric measurements. Figure 4: AutoCAD measures of Delta Cephei components, in- cluding DAL 45 (DE) The measuring process involved choosing several reference stars from the selected frame and taking pho- tometric brightness (or intensity) readings for each. “Lucky ” image of the pair. The relative intensity values along with the known One aspect of the enlarged photo that struck us im- magnitudes of the reference stars can then be used to mediately was the apparent unequal brightness of the calculate the magnitude of an unknown star using the pair. According to Daley’s measurements the compo- relationship: nents were nearly a matched set (magnitudes 13.9 & 14.0) with the southernmost (D) being the brighter of the two. It is tempting to speculate that perhaps the difficulty I had in capturing the pair was in part due to a dimming of one of the components, but it also could Where M1 = known magnitude of reference star 1, be simply a byproduct of the extreme processing used M2 = unknown magnitude of Star 2, and I1 / I2 = meas- on the tiny image. In any event I was not able to cap- ured photometric intensities of stars 1 and 2. ture enough images with sufficient clarity to confirm or Six reference stars in close proximity to DAL 45

Figure 5. DAL 45 at original resolution of 1.0 arc-sec/pixel (left) and the same image (middle & right) resampled (8x) and processed to enhance the image (~0.13 arc-sec per pixel)

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In Search of DAL 45: Observing on the Edge with a 4 Inch Refractor

were located on the photographic frame using the AL- ADIN Sky Atlas program and the UCAC4 Star Cata- log. The selected reference stars (shown in Figures 6 and 7) have visual magnitudes close to the tabulated values of DAL 45 in order to reduce any possible ef- fects of non-linearity of the camera sensor when re- cording such faint objects. The measured photometric intensity for the com- bined image of Dal 45 (D + E) was 978. The meas- ured photometric intensities of the reference stars and the resulting calculated magnitudes for DAL 45 are shown in Table 1. Not surprisingly, and confirming the visual im- pression from the photographs, the calculated 14.4 magnitude is a half magnitude fainter than Daley’s Figure 6. Photometric Comparison Stars 13.9 magnitude value and nearly a full magnitude faint- er than F and explains the difficulty I was having in photographing this system. As a further check on the Table 1. Photometric Data Used For Calculating the accuracy of these measurements, the magnitude of each Magnitude of DAL 45 of the reference stars was checked against the other 5 reference stars using the same methodology with the Comparison Stars UCAC4 Photometric Calculated results shown in Table 2. (UCAC4) V Mag Intensity DAL 45 Mag The standard deviation of the tabulated magnitudes 742-080074 13.998 1630 14.393 versus the calculated magnitudes was only 0.21, which 743-079494 12.740 4517 14.242 lends confidence to the reference magnitudes and the intensity measures used in the comparison. So the low- 743-079502 13.900 1987 15.510 er magnitude estimate from my measurements for DAL 743-079594 14.742 1149 14.140 45 seems to be both real and significant. Table 3 is a 743-079607 14.125 1401 14.421 summary of the various magnitude measurements of 743-079609 14.190 1073 14.683 DAL 45 and show the variation in the measured magni- Average = 14.398 tudes which are in part, no doubt, due to the differences Std Dev = 0.176 in the photometric bandpass filters used in the measure- ments. Not surprisingly my measure seems to align Std Mean Err = 0.072 best with the UCAC4 measure since my unfiltered ex- posures can be assumed to be most sensitive to the V band and that I used the UCAC4 catalog values as the source for my standard reference magnitudes. So in the end DAL 45 ended up being much more Table 2. Photometric Data for Checking the Magnitude of challenging than expected – according to my meas- the Calibration Stars urements with a combined magnitude of 14.4 and a Avg Calcu- Comparison Stars UCAC4 V Magnitude separation of 1.43 arc-sec it will present a challenge to lated Magni- (UCAC4) Mag Difference just about any amateur telescope no matter the aper- tude ture. James Daley used an 8 inch refractor with 4 times 742-080074 13.998 14.004 0.006 the light gathering power of my 4 inch scope to make his original measurements and I am surprised at the 743-079494 12.740 12.928 0.188 detail I was able to collect using my modest 4 inch re- 743-079502 13.900 13.766 -0.134 fractor and some amazing software, but for now will 743-079594 14.742 14.400 -0.342 leave it to more capable instruments to further observe 743-079607 14.125 14.434 0.309 and measure this system. 743-079609 14.190 14.163 -0.027 Avg Difference = 0.000 Std Dev = 0.211 Std Mean Err = 0.094

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In Search of DAL 45: Observing on the Edge with a 4 Inch Refractor

Figure 7. Closeup - DAL 45 & Comparison Stars

Table 3. DAL 45 – Historical Magnitudes Source Date DE Magnitude Comments 2MASS 1999 11.94 F mag - Avg of 3 frames UCAC4 2003 14.44 V-R mag J. Daley 2008 13.90 B-V mag S. Smith 2013 14.40 V (Unfiltered) Postscript 1-31-14 Web Sites Just prior to submitting this article I discovered that 2MASS Point Source Catalog. 2003 all-sky release an additional 4 components were added to the listing (TMA2003) http://www.ipac.caltech.edu/ 2mass/ for Delta Cephei (FYM 115 G thru J) ranging in mag- releases/allsky/ nitude from 12 to 13.5. For now DAL 45 still remains the most elusive member of the Delta Cephei family. ALADIN Sky Atlas: http://aladin.u-strasbg.fr/ aladin.gml References Double Star Imaging Group: http://groups.yahoo.com/ “Ludwig Schupmann Observatory Measures of Large neo/groups/double_star_imaging  m Pairs”, Daley, J., 2009, JDSO, 3, 149-154. IRIS - Astronomical Images Processing Software, Ver- “Double Stars in the USNO CCD Astrographic Cata- sion 5.59. www.astrosurf.com log” (UC_2013b), Hartkopf, W.I., Mason, B.D., et. al., Astronomical Journal 146, 76, 2013. SIMBAD Astronomical Database: http://simbad.u- strasbg.fr/simbad/ “Washington Double Star Catalog”, Mason, Brian., 2013, http://ad.usno.navy.mil/wds/ Stelladoppie WDS Interface: http:// stelledoppie.goaction.it/index2.php?section=1

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Double Star Observations with a 150mm Refractor in 2013

Marc Oliver Maiwald Witten, Germany [email protected]

Abstract: I present 144 observations of 76 double stars made in 2013 with a 150 mm re- fractor. Residuals were computed for selected double stars.

The equipment and observing techniques used were CCD Camera in 2010", Journal of Double Star Ob- the same as in previous years (Maiwald, 2013). Again servations, 7, 78 – 85, 2011. the 150/3000mm folded refractor and the DMK 21 Argyle, Bob, "Micrometer measures of northern double black and white camera were used. A 1.4x stars in 2010", The Webb Society Double Star Sec- Teleconverter was added to the equipment. The optical tion Circular No. 19, 2011, 1 – 3. http:// configurations used in 2013 were: Teleconverter 2x: www.webbdeepsky.com/ 0.19876 a.s. per pixel (labeled TK2 in the tables.); Teleconverter 1.4x: 0.297322 a.s. per pixel (TK1.4 in Argyle, Bob, "Micrometer measures of double stars in the tables); focal: 0.384 a.s. per pixel (f in the tables). 2011", The Webb Society Double Star Section Cir- Observations made in 2013 with some from early 2014 cular No. 20, 2012, 1 – 4. http:// are listed in Table 1. www.webbdeepsky.com/ For some of the measured pairs weighted averages were calculated and compared with the ephemeris. The Argyle, Bob, "Micrometer measures of double stars in calculations were done with Calculator 2012", The Webb Society Double Star Section Cir- (Workman, 2013) using data from the “Sixth Catalog of cular No. 21, 2013, 1 – 4. http:// of Visual Binary Stars”. The residuals are listed www.webbdeepsky.com/ in Table 2. Courtot, Jean – Francois, "Micrometer measures of Acknowledgements double stars in 2012", The Webb Society Double Star Section Circular No 21, 2013, 4 – 5. This paper made extensive use of the Washington Double Star Catalog and the Sixth Catalog of Orbits of Hartkopf, William I., Mason, Brian D., Sixth Catalog of Visual Binary Stars, both maintained at the U.S. Naval Orbits of Visual Binary Stars. http:// Observatory. Noncommercial Software used was: Bina- ad.usno.navy.mil/wds/orb6.html ry Star Calculator by Brian Workman; Giotto 2.12 by Maiwald, Marc Oliver, "Double Star Measurements Georg Dittié; Reduc 3.88 by Florent Losse and Using a Small Refractor", Journal of Double Star Registax 4 by Cor Berrevoets. Observations, 9, 189 – 194, 2013. References Prieur, J. - L., M. Scardia, L. Pansecchi, R. W. Argyle, Anton, Rainer, "Double and multiple star measurements M. Sala, "Speckle Observations with PISCO from at the northern sky with a 10"-Newtonian and a fast (Continued on page 192)

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Double Star Observations with a 150mm Refractor in 2013

Table 1. Double Star observations in 2013

Designation WDS θ ρ Date No Name Notes

355.4 1.48 2013.946 32 TK2 STF3062 00063+5826 353.9 1.47 2013.949 27 TK2

353.7 1.51 2013.971 32 TK2 352.1 1.5 2013.985 31 TK2 STF 12 00150+0849 147.2 11.42 2013.87 45 35 Psc TK1.4 AC 1 00209+3259 287.1 1.87 2013.903 26 TK1.4

286.8 1.85 2013.913 17 TK1.4 STF 60AB 00491+5749 323.8 13.26 2013.922 47  Cas TK1.4 323.8 13.28 2013.924 36 TK1.4 STF 61 00499+2743 295.2 4.28 2013.87 17 65 Psc TK1.4 327.9 0.99 2013.903 79 TK2 STF 73AB 00550+2338 329.1 0.98 2013.922 35 36 And TK2 327.4 1.12 2013.924 29 TK2 329.6 1.04 2013.944 40 TK2 STF 79 01001+4443 194.1 7.9 2013.87 42 TK1.4 STF 174 01501+2217 163.3 2.9 2013.985 33 1 Ari TK1.4 164.8 2.9 2013.996 33 TK1.4 0.1 7.46 2013.985 40 TK1.4 STF 180AB 01535+1918  1.9 7.45 2013.996 22 Ari TK1.4

1.1 7.45 2014.007 18 TK1.4 STF 222 02109+3902 35.8 16.69 2013.949 18 59 And TK1.4 35.8 16.68 2013.971 45 TK1.4 STF 262AB 02291+6724 229.8 2.81 2013.944 47  Cas TK1.4 230.2 2.86 2013.971 33 TK1.4 115.9 7.18 2013.944 42  TK1.4 STF 262AC 02291+6724 Cas 115.4 7.11 2013.971 20 TK1.4 298.9 2.03 2013.924 61 TK2  STF 299 02433+0314 298.5 1.92 2013.944 53 Cet TK2 297.7 2.07 2013.946 59 TK2

211 1.22 2013.985 44 TK1.4  STF 333AB 02592+2120 210.7 1.54 2013.996 35 Ari TK1.4 208.8 1.36 2014.007 36 TK2

STF 900AB 06238+0436 29.2 12.27 2013.133 35 8 Mon f

55.6 4.9 2013.133 47 f  STF1110AB 07346+3153 55.6 4.7 2013.177 44 Gem TK2 55.7 4.79 2013.199 80 TK2 26.4 0.97 2013.177 47  TK2 STF1196AB 08122+1739 Cnc 27.6 1.12 2013.314 39 TK2 63.5 6.32 2013.177 28  TK2 STF1196AC 08122+1739 Cnc 63.2 6.29 2013.314 49

Table 1 continues on next page.

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Double Star Observations with a 150mm Refractor in 2013

Table 1 (continued). Double Star observations in 2013

Designation WDS θ ρ Date No Name Notes

308.5 0.98 2013.177 22 TK2 STF1338AB 09219+3811 307.4 1.08 2013.314 21 TK2 176.7 1.44 2013.267 36 TK2 STT 215 10163+1744 176 1.43 2013.339 42 TK2 125.7 4.65 2013.237 36 f STF1424AB 10200+1950  125.9 4.64 2013.341 34 Leo TK2

STF1487 10556+2445 112.5 6.43 2013.267 45 54 Leo TK2

STF1521 11154+2734 97.5 3.54 2013.267 21 TK2

187.5 1.6 2013.347 80  TK2 STF1523AB 11182+3132 Uma 188.3 1.64 2013.396 43 TK2 9.9 1.92 2013.339 20  TK2 STF1670 12417-0127 Vir 9.7 1.99 2013.341 21 TK2 95.3 1.71 2013.396 42 TK2 94.3 1.69 2013.421 32 TK2 STF1768AB 13375+3618 25 CVn 95.9 1.7 2013.424 46 TK2 95.5 1.65 2013.429 38 TK2

STF1821 14135+5147 235.6 13.62 2013.443 35  Boo TK1.4 STF1835AB 14234+0824 194.6 6.06 2013.432 33 TK2 STF1864AB 14407+1625 111.3 5.48 2013.38 12  Boo TK2 STF1884 14484+2422 54.3 2.01 2013.454 38 TK2 STF1890 14497+4843 46.3 2.58 2013.424 28 39 Boo TK2 303.7 5.71 2013.38 27 TK2 STF1888AB 14514+1906  304.5 5.65 2013.432 38 Boo TK2 161.2 1.11 2013.432 14 TK2 STT 288 14534+1542 159 1.03 2013.454 32 TK2 63 1.28 2013.38 69 TK2 STF1909 15038+4739 63.1 1.28 2013.421 67 44 Boo TK2 63.2 1.25 2013.434 63 TK2 STF1932AB 15183+2650 264.3 1.59 2013.443 15 TK2 STFA 28AB 15245+3723 171 108.96 2013.457 39  Boo TK1.4 4.6 2.27 2013.457 43 TK1.4 STF1938BC 15245+3723 3.7 2.28 2013.481 48  Boo TK1.4 4.4 2.28 2013.495 32 TK1.4 STF1965 15394+3638 305.8 6.38 2013.495 37  CrB TK1.4 238.1 7.21 2013.481 43 TK1.4 STF2032AB 16147+3352  238 7.19 2013.495 29 CrB TK1.4 65.9 0.93 2013.514 62 TK2 STF2118AB 16564+6502 20 Dra 64.6 0.9 2013.522 42 TK2 4.2 2.52 2013.511 41 TK 1.4 STF2130AB 17053+5428 4.6 2.38 2013.511 18  Dra TK 2 4.1 2.41 2013.514 29 TK 2

Table 1 continues on next page.

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Double Star Observations with a 150mm Refractor in 2013

Table 1 (continued). Double Star observations in 2013

Designation WDS θ ρ Date No Name Notes 103.4 4.64 2013.533 29  TK2 STF2140AB 17146+1423 Her 103.3 4.84 2013.541 40 TK1.4 STF2161AB 17237+3709 320.2 4.09 2013.498 38  Her TK1.4 55.6 2.01 2013.533 14 TK2 STF2199 17386+5546 54.7 2.06 2013.55 12 TK2 310.7 1.45 2013.55 31 TK2 STF2218 17403+6341 310.4 1.45 2013.552 35 TK2 127.5 6.17 2013.498 47 TK1.4 STF2272AB 18055+0230 70 Oph 127.6 6.24 2013.519 43 TK1.4 222.1 1.26 2013.539 21 TK2 STF2289 18101+1629 222.4 1.22 2013.547 40 TK2 148.8 1.62 2013.519 17 TK2 STT 358 AB 18359+1659 149.3 1.59 2013.528 27 TK2 STF2362 18384+3603 187 4.37 2013.528 47 TK1.4 STF2368 18389+5221 320.7 1.91 2013.552 8 TK2 STF2380 18429+4456 8.1 25.7 2013.539 37 f 346 2.23 2013.517 27  TK2 STF2382AB 18443+3940 Lyr 346.7 2.25 2013.522 41 TK2 78 2.29 2013.517 44 5 Lyr TK2 STF2383CD 18443+3940 77.3 2.32 2013.522 37 TK2 STFA 38 18448+3736 149.8 43.68 2013.539 37  Lyr f STF2470 19088+3446 267.3 13.86 2013.588 10 TK1.4 STF2474AB 19091+3436 262.9 15.91 2013.588 9 TK1.4 STTA181AB 19201+2639 359.6 63.03 2013.593 10 f STF2486AB 19121+4951 204.6 7.22 2013.571 37 TK2 218.2 2.63 2013.555 35  TK2 STF2579AB 19450+4508 Cyg 218 2.53 2013.604 32 TK2 102.6 1.38 2013.555 30 TK2 STF2583 19487+1149  102.9 1.34 2013.569 37 Aql TK2 175.1 2.8 2013.577 26  TK2 STF2605AB 19556+5226 Cyg 177 2.74 2013.648 40 TK2 22.5 1.87 2013.61 34 TK2 STF2609 19586+3806 22.3 1.95 2013.626 32 TK2 172.7 1.9 2013.599 31 TK2 STF2624AB 20035+3601 173.8 1.87 2013.621 45 TK2 174.6 1.97 2013.626 36 TK2 339.6 2.91 2013.569 16 TK2 STF2628 20078+0924 340.1 2.84 2013.582 17 TK2 STF2671AB 20184+5524 337.5 3.65 2014.648 40 TK2 44.6 2.7 2013.637 33 TK1.4 STF2716AB 20410+3218 49 Cyg 43.5 2.62 2013.64 35 TK2

Table 1 concludes on next page.

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Double Star Observations with a 150mm Refractor in 2013

Table 1 (conclusion). Double Star observations in 2013

Designation WDS θ ρ Date No Name Notes

STF 2727 20467+1607 265.5 9 2013.684 38  Del TK1.4 25.6 1.9 2013.64 29 TK2 STF 2741 AB 20585+5028 25.4 1.99 2013.744 26 TK1.4

356.9 1.68 2013.634 19 TK1.4 STF 2751 21021+5640 355.2 1.64 2013.637 37 TK1.4 356.5 1.59 2013.64 35 TK2

152.1 31.43 2013.637 34 61 Cyg TK1.4 STF 2758 AB 21069+3845 152.1 31.48 2013.662 32 61 Cyg TK1.4 299.2 18.14 2013.815 48 f STF 2769 21105+2227 299.2 18.1 2013.82 34 f 20.6 2.49 2013.662 36 TK1.4 STT 437 AB 21208+3227 19.8 2.49 2013.744 32 TK1.4 59.8 149.56 2013.815 32 f S 799 AB 21434+3817 79 Cyg 59.6 149.55 2013.82 19 f

315.3 1.75 2013.662 38 TK1.4 317.5 1.7 2013.744 38 TK1.4 STF 2822 AB 21441+2845  318 1.73 2013.798 48 Cyg TK1.4 317 1.64 2013.798 43 TK2

165.6 2.28 2013.869 57  TK1.4 STF 2909 22288-0001 Aqr 165.1 2.25 2013.903 78 TK1.4 338.5 2.29 2013.922 24 TK2 STF 3050 AB 23595+3343 338.2 2.39 2013.944 40 TK2

Table 2 begins on next page.

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Double Star Observations with a 150mm Refractor in 2013

Table 2. Residuals for double stars in 2013

Designation WDS Name Date θ ρ Δθ Δρ Ref.; Notes STF3062 00063+5826 2014.0 353.8 1.49 -0.4 -0.06 Sod1999 STF 60AB 00491+5749  Cas 2013.9 323.8 13.27 0.6 -0.04 Str1969a STF 73AB 00550+2338 36 And 2013.9 328.4 1.01 0.3 -0.11 Doc1990b STF 262AB 02291+6724  Cas 2013.9 230 2.83 1.7 0.22 Hei1996b; 1 STF 333AB 02592+2120  Ari 2014.0 210.2 1.36 0.6 0.01 FMR2012g STF1110AB 07346+3153  Gem 2013.2 55.6 4.8 -0.2 -0.12 Hei1988a STF1196AB 08122+1739  Cnc 2013.2 26.9 1.04 0.7 -0.06 WSI2006b STF1338AB 09219+3811 2013.2 308 1.03 -1.8 0.02 Sca2002b; 2 STT 215 10163+1744 2013.3 176.3 1.42 -2.4 -0.13 Zae1984; 3 STF1424AB 10200+1950  Leo 2013.3 125.8 4.56 -0.3 -0.06 WSI2006b STF1523AB 11182+3132  Uma 2013.4 187.8 1.61 0.7 -0.07 Msn1995 STF1670 12417-0127  Vir 2013.3 9.8 1.96 -0.5 -0.04 Sca2007a STF1768AB 13375+3618 25 CVn 2013.4 95.3 1.69 -0.3 -0.02 Sod1999 STF1888AB 14514+1906  Boo 2013.4 304.2 5.67 -0.6 -0.1 Sod1999 STT 288 14534+1542 2013.4 159.7 1.05 -0.1 0.02 Hei1998 -0.5 0.12 Sod1999; 4 STF1909 15038+4739 44 Boo 2013.4 63.1 1.27 -1.2 0.06 Zir2011 STF1932AB 15183+2650 2013.4 264.3 1.59 -0.3 -0.03 Sca2013b STF1938BC 15245+3723  Boo 2013.5 4.2 2.28 -0.1 0.06 Sca2013a STF2032AB 16147+3352  CrB 2013.5 238.1 7.2 0.1 0.04 Rag2009 STF2118AB 16564+6502 20 Dra 2013.5 65.4 0.92 -1.6 -0.23 Sca2002d STF2130AB 17053+5428  Dra 2013.5 4.3 2.46 -0.2 -0.01 Pru2012 STF2140 17146+1423  Her 2013.5 103.3 4.76 0.1 0.12 Baz1978 STF2199 17386+5546 2013.5 55.2 2.03 2 0.1 Pop1995d STF2272AB 18055+0230 70 Oph 2013.5 127.5 6.2 0.4 0.04 Pbx2002b STF2289 18359+1659 2013.5 222.3 1.23 6.3 -0.01 Hop1964b; 5 STT 358AB 18359+1659 2013.5 149.1 1.6 1.7 0.08 Hei1995 -0.1 -0.12 WSI2004b STF2382AB 18443+3940  Lyr 2013.5 346.4 2.24 -0.1 -0.05 Nov2006e STF2383CD 18443+3940 5 Lyr 2013.5 77.7 2.3 0.9 -0.08 Doc1984b STF2486AB 19121+4951 2013.5 204.6 7.22 0.1 -0.05 Hle1994 STF2579AB 19450+4508  Cyg 2013.6 218.1 2.58 0 -0.13 Sca2012c STF2727 20467+1607  Del 2013.7 265.5 9 0.4 0 Hle1994 STF2758AB 21069+3845 61 Cyg 2013.6 152.1 31.45 0.4 -0.02 Pko2006b STT 437AB 21208+3227 2013.7 20.2 2.49 1.1 -0.07 Hrt2011a STF2822AB 21441+2845  Cyg 2013.8 317 1.7 -2.9 0.12 Hei1995; 6 STF2909 22288-0001  Aqr 2013.8 165.3 2.26 -1.1 0.04 Sca2010c; 7 STF3050AB 23595+3343 2013.9 338.3 2.35 -0.5 0.01 Hrt2011a

Notes for Table 2 begin on next page.

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Double Star Observations with a 150mm Refractor in 2013

Table 2 Notes

1. STF 262 AB is known for periodic deviations, probably caused by an unseen component. 2. This star is at the limit of what can be measured with my equipment. Position and residues for the years 2010 to 2012 were calculated from measurements in (Maiwald, 2013). A large negative Δθ was also reported in (Courtot, 2013) for 2012.235.

Table 3. Residuals for STF 1338 2010 - 2013

Designation WDS Nights Date θ ρ Δθ Δρ Reference 2 2010.3 299.3 0.99 -5.4 -0.02 1 2011.2 301.4 0.9 -4.9 0.06 STF1338AB 09219+3811 Sca2002b 1 2012.2 306 1.07 -2 -0.08 2 2013.2 308 1.03 -1.8 0.02 3. In (Prieur et al., 2012) from speckle interferometry residuals for 2010,264 Δθ –1,6 and Δρ –0,08 for the same were given. 4. It was fascinating to follow the rapid motion of this double. In Table 4 observations from the years 2009 to 2013 are given with residuals for two orbits. Observation from 2009 was previously unpublished. Position and residuals for the years 2010 to 2012 were calculated from measurements in (Maiwald, 2013). For a de- tailed study see (Zirm, 2011).

Table 4. Residuals for STF 1909 2009 - 2013

Sod 1999 Zir 2011 Designation WDS Nights Date θ ρ Δθ Δρ Δθ Δρ 1 2009.4 59.9 1.65 0.8 -0.02 0.1 -0.02 1 2010.4 60.2 1.62 0.2 0.06 -0.6 0.05 STF1909 15038+4739 3 2011.4 60.5 1.45 -0.5 0.01 -1.29 -0.01 4 2012.4 61.9 1.36 -0.2 0.06 -1 0.02 3 2013.4 63.1 1.27 -0.5 0.12 -1.2 0.06

5. Large scatter in θ in published measurements (Anton, 2011), (Scardia et al., 2013), (Wiley, 2013), but all deviate from the ephemeris 6. STF 2822 is known for deviations from ephemeris. Position and residuals for 2010 to 2012 again from data in (Maiwald, 2013). In (Prieur et al., 2012) Δθ = –3.3 for 2011.756 is given, in (Argyle, 2012) Δθ = –2.1 for 2011.989. Table 5. Residuals for STF 2822 2010 - 2013

Designation WDS Nights Date θ ρ Δθ Δρ Reference 1 2010.6 312 1.8 -4.9 0.16 1 2011.7 315.2 1.69 -2.7 0.07 STF2822AB 21441+2845 Hei1995 1 2012.7 316.1 1.69 -2.8 0.09 4 2013.8 317 1.7 -2.9 0.12

7. The new orbit gives smaller, but still rather large residuals. Position and residuals for 2010 to 2012 again from data in (Maiwald, 2013). Somewhat larger residuals for the newer orbit were reported by (Argyle, 2011), (Argyle, 2012), (Argyle, 2013).

Table 6. Residuals for STF 2909 2010 - 2013 Sca2010c Hei1984c Designation WDS Nights Date θ ρ Δθ Δρ Δθ Δρ 1 2010.8 168.1 2.21 -1.9 0.06 -2.4 -0.03 1 2011.8 168.3 2.1 -0.7 -0.07 -1.1 -0.17 STF2909 22288-001 1 2012.8 166.7 2.17 -1 -0.03 -1.5 -0.13 2 2013.8 165.3 2.26 -1.1 0.04 -1.8 -0.07

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Double Star Observations with a 150mm Refractor in 2013

(Continued from page 185) Merate: XI. astrometric measurements of visual bi- naries in 2010", Monthly Notices of the Royal As- tronomical Society, 422, 1057 – 1070, 2012. Scardia, M., J. L. Prieur, L. Pansecchi, R. W. Argyle, P. Spanò, M. Riva, M. Landoni, "Speckle Observations with PISCO from Merate: XII. astrometric measurements of visual binaries in 2011", Monthly Notices of the Royal Astronomical Society, 434, 2803 – 2822, 2013. Wiley, E.O., "A Pixel Correlation Technique for Smaller Telescopes to Measure Doubles", Journal of Double Star Observations, 9, 142 – 152, 2013. Workman, Brian, "Binary Star Calculator", http:// www.saguaroastro.org/content/db/ binaries_6th_Excel97.zip Zirm, Henry, "The Rapid Convergence of 44 Boötis with Revised Orbit and Updated Ephemeris", Jour- nal of Double Star Observations, 7, 24 – 36, 2011.

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Analysis of Errors in the Measurement of Double Stars Using Imaging and the Reduc Software

Tim Napier-Munn and Graeme Jenkinson Astronomical Association of Queensland

Abstract: This paper reports quantification and explanation of some sources of error in using the Reduc software to measure the PA and separation of double star images. A comparison of measures of the images of two pairs, one close and one wider, made by the two authors inde- pendently has shown that the two individuals produce measurements that are numerically nearly identical and are not significantly different statistically. Analysis of the repeated measures of 38 pairs has shown that the standard deviation of PA increases with decrease in separation due mainly to the geometry of the measurement. The standard deviation of separation increases with separation due mainly to propagation of the error in determining the separation calibration constant. All these errors can be controlled to any desired precision by conducting sufficient repeats.

refractor. In some cases of close separations a Barlow Introduction lens was used (either 2.36x or 5.43x). Separations and The Astronomical Association of Queensland is position angles were measured using the software pro- undertaking a program of measuring neglected double gram Reduc (Losse), which was specifically designed and multiple stars visible from Queensland at an ap- to measure double stars using appropriate images of the proximate latitude of 27ºS. “Neglected” was arbitrarily target pairs together with images of calibration pairs of defined as 15 or more years since the last measure as known separation and PA; Argyle’s list of calibration recorded in the Washington Double Star catalog pairs was used for this purpose (Argyle, 2004). (WDS). Results to date have been reported in the In order to obtain statistically viable results, the Webb Society Double Star Section Circulars 17 and 18 DSI software is used to stack a minimum of 10 individ- (Napier-Munn and Jenkinson; 2009, 2010), and further ual good quality images as they are acquired, to gener- reports are in preparation. ate one image for measuring. About 10 such images The method involves acquiring an image of the are obtained per pair per night, plus 3 trailed images chosen pair and measuring position angle and separa- with the tracking switched off in order to calibrate the E tion using Florent Losse’s Reduc software (see Losse). -W axis in the images. The Reduc software is then In our 2009 paper we evaluated the errors associated used to generate a single average measure for the 10 with the estimation of the separation constant (specific images. This process is repeated on about 7 separate to the camera and optical train) and the PA constant nights, generating mean separations and position angles (depending on the orientation of the camera with re- together with standard deviations from which a confi- spect to the sky). In this paper we take advantage of dence interval for the measurement can be calculated some recent measurements to comment on the magni- based on the 7 repeat values. There is therefore a con- tude of personal errors by comparing the measurements siderable amount of replication built into the final PA of the two authors on the same images. We also inves- and separation values. A full description of the method tigate the dependencies of the measurement uncertain- was given in Napier-Munn and Jenkinson (2009). ties in PA and separation on the separation itself. Florent Losse’s excellent software has a built-in Method automated procedure which greatly decreases the time needed to make measurements, and this works well for All images were obtained using a Meade DSI CCD easy pairs, that is those with wide separations in barren camera coupled to an equatorially-mounted 150mm f8

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Analysis of Errors in the Measurement of Double Stars Using Imaging and the Reduc Software

Table 1. Measures of HRG 53 Car

PA ° Separation " Date Jenkinson Napier-Munn Jenkinson Napier-Munn 11-Feb-10 215.39 212.20 3.265 3.173 14-Feb-10 210.60 212.95 3.244 3.106 19-Feb-10 216.99 218.38 3.287 3.193 20-Feb-10 219.53 218.83 3.201 3.200 21-Feb-10 218.30 217.95 3.127 3.247 26-Mar-10 218.54 216.36 3.253 3.216 Mean 216.56 216.11 3.230 3.189 Std. Dev. 3.251 2.873 0.058 0.048 Coeff. of var. % 1.50 1.33 1.79 1.50 95% conf. int. ± 3.412 3.015 0.061 0.050 WDSC entry: RA 10 52.4 Dec -58 45 Mags 8.4 & 10.2 PA 218° Sep 3.6" (1991) Im- aged with 5.43x Barlow. Measured using Reduc’s QuadPx facility. One night’s measures rejected because of poor seeing and degraded images (not shown in Table 1)

fields. However, quite often manual measurements Reduc’s automated procedure. are required which are subject to some degree of per- Observations of these two pairs suggested some sonal error in identifying the position of each star, or interesting relationships between measurement uncer- more specifically the center of each star’s image. In tainties and the separation itself, and these were fur- this paper, therefore, we turn our attention to the ef- ther investigated using data from earlier measurements fects of personal error on the measurement uncertain- of 36 pairs, plus the two mentioned above, 38 in all. ties by comparing the values obtained by the two au- thors on the same images. The test pairs for this com- Results parison were HRG 53 in Carina and HJ 4583 in Cen- Results for the two test pairs are shown in Tables taurus. HRG 53 is a close pair (around 3" separation) 1 and 2, including the current WDS entry (as of Janu- and HJ 4583 a wider pair (around 23" separation). All ary 2014). Barlows were used in both cases, for measurements were made manually, that is, not using which separate separation calibrations were required.

Table 2. Measures of HJ 4583 Cen

PA ° Separation " Date Jenkinson Napier-Munn Jenkinson Napier-Munn 21-Apr-12 173.23 173.26 21.437 21.443 11-May-12 172.76 172.75 21.402 21.669 12-May-12 173.59 173.54 21.573 21.530 18-May-12 172.35 172.40 21.298 21.651 15-Jun-12 171.95 171.89 21.807 21.726 30-Jun-12 171.61 171.71 22.148 22.104 06-Jul-12 171.88 171.91 21.924 21.913 Mean 172.48 172.49 21.656 21.719 Std. Dev. 0.740 0.716 0.312 0.225 Coeff. of var. % 0.43 0.42 1.44 1.04 95% conf. int. ± 0.685 0.751 0.289 0.237

WDSC entry: RA 13 25.2 Dec -64 29 Mags 5.3 & 11.0 PA 180° Sep 21.8" (1997) Imaged with 2.36x Barlow.

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Analysis of Errors in the Measurement of Double Stars Using Imaging and the Reduc Software

Table 3 – Comparison of means of measures by the two observers

HRG 53 (n = 6)* HJ 4583 (n = 7)* Statistic PA ° Separation " PA ° Separation "

Mean difference between observers 0.45 0.04 0.01 0.06

SD of difference between observers 2.09 0.09 0.06 0.17 95% confidence interval of 2.19 0.10 0.05 0.16 difference ± Paired t-test 2-sided P-value 0.62 0.33 0.57 0.36

* n = number of measures by each observer

In the case of the close pair (HRG 53) Reduc’s Dependency of measurement uncertainty on separa- QuadPx facility was used to magnify the image before tion measurement; this resamples the displayed image and Inspection of Tables 1 and 2 shows that the stand- enlarges it by a factor of two while keeping the distri- ard deviations of the PA measurements for the close bution of the light constant by unit of area. double HRG 53 (mean sd 3.06°) were much larger The data for the subsequent study of the depend- than those for the wider pair HJ 4583 (mean sd 0.73°). ence of measurement uncertainty on separation are Conversely the standard deviations of the separation taken from Napier-Munn and Jenkinson (2009, 2010) measurements for the close double (mean sd 0.053") and from the authors’ unpublished data (report in were much smaller than those of the wider pair (mean preparation), together with the two measures presented sd 0.269"). F-tests on the variances confirm that these above, 38 doubles in all. are statistically significant differences. This suggests that there are systematic variations in measurement Discussion uncertainty as a function of the separation of the pair. Comparison of measurers Figure 1 shows the relationship between the stand- Tables 1 and 2 show very close agreement be- ard deviation of the PA measurement and the meas- tween the two observers, their mean results being ured separation for the 38 pairs measured by the au- nearly identical for both PA and separation. The thors. Although there is a good deal of scatter there is paired t-test was used to test the hypothesis that the a clear relationship which is linear on log axes. The PA and separation measures of the two observers were fitted power function is shown in the figure; regres- not significantly different. Table 3 summarizes the sion statistics show that it is statistically significant. results. This confirms that the uncertainty in the PA measure- By convention a P-value of 0.05 or less would be ment increases as the separation decreases, and the considered as evidence in favor of the alternative hy- rate of increase is high at small separations. pothesis that the measures of the two observers were This is to be expected if we assume that the uncer- different. In all four comparisons (PA and separation tainty in measuring the position of each star center is for each double) P is much greater than 0.05 and we constant across the image and that the uncertainty in may therefore conclude that there is no evidence that the PA exists in only one dimension, perpendicular to the measures of the two observers are statistically dif- the line joining the two centers. If we consider the ferent. This is confirmed by the confidence intervals range of possible positions of the secondary as a proxy on each difference which all include zero. for uncertainty, then it is easy to show that the range Also of interest is the precision (repeatability) of of uncertainties in angle must be inversely related to each observer, which can be compared by comparing the distance, as in Figure 1. The principle is illustrat- the ratio of the variances (i.e., the square of the stand- ed in Figure 2, which shows how the angle describing ard deviations in Tables 1 and 2) of the two observers the uncertainty in PA (of the secondary relative to the using an F-test. Again this shows no statistical differ- primary) varies with separation. In this simple dia- ence between the observers, with 2-sided P-values in gram tan = r/d where r is half the range of uncertain- the range 0.45 – 0.94. ty, d is the separation, and  is the half angle corre- sponding to the maximum range of uncertainty (we

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Analysis of Errors in the Measurement of Double Stars Using Imaging and the Reduc Software

Figure 1. Standard deviation of PA measurement (°) vs measured separation (") for 38 pairs. are dealing in half angles because for clarity the mirror with which the center of each star can be determined. image of the diagram is not shown). Thus we would However, the regression statistics show that the fitted expect an inverse relationship between separation and model is statistically significant and that the increase PA uncertainty, which is indeed what we see in Figure of separation standard deviation with standard devia- 1. (Of course the uncertainties illustrated in Figure 2 tion is real. It is likely that this is at least partly due to apply to the primary as much as to the secondary but the propagation of the error inherent in the calibration the net effect will be the same). factor, E, which is obtained by measuring pairs of The dependency of the separation standard devia- known separation. In our case we used three Barlow tion upon the mean separation is also worth noting, configurations: no Barlow, a x2.36 Barlow and a shown in Figure 3. The data have been plotted on a x5.43 Barlow. E was calculated for each configura- log x-axis, and a power law model fitted shown by the tion together with the variance of E based on many solid line. repeat measurements of several calibration pairs. As in Figure 1, there is considerable scatter due to The Reduc software calculates the separation, d, factors not captured in the two-factor plot, including as the number of pixels between the star centers in the the use or otherwise of the QuadPx facility in Reduc image, n, times the calibration factor, E. As there is and the prevailing seeing which controls the precision likely to be little or no error in counting the number of

Figure 2. Relationship between the separation (d) and the angle defining the maximum range of uncertainty in determining the position of the secondary component ()

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A New Visual Double Star in Gemini

Figure 3. Standard deviation of separation measurement (") vs measured separation for 38 pairs. Continuous line is fitted function; dotted line is theoretical prediction (eqn 2).

pixels (other than the error in locating the star centres standard deviation of PA or separation and the magni- which could be significant especially with degraded tudes of either component or their difference. images in poor seeing), the uncertainty in d is likely to be due mainly to the variance in E summed over the Conclusions number of pixels between the centers. Thus, An error analysis has been conducted of repeated measures of some southern doubles using the Reduc software to determine PA and separation from stacked (1) images. This adds to earlier analysis by the authors of the errors inherent in determining the PA and separa- 2 2 tion constants in Reduc (Napier-Munn and Jenkinson, where d = separation variance, E = calibration con- stant variance, and n = number of pixels between the 2009). star centres. As n = d/E, then It has been shown that independent measures of the same images for two pairs, one close and one more distant, by the two authors give results which are to all intents and purposes identical. We therefore conclude (2) that application of Reduc by competent users should include a negligible component of personal equation, even in the application of the manual option in Reduc. This value of the predicted separation standard Analysis of the repeated measures of 38 pairs shows clearly that the uncertainty in the estimate of deviation, d , from equation 2 is plotted against the PA increases as the separation decreases. This is at- separation, d, as the dotted line in Figure 3, using the tributed to the simple geometry of the measurement average prediction of the three Barlow conditions process, whereby a constant uncertainty in the position (each having different values of E and E). The agree- of the stars’ centres has much more effect at small ment is good. Although this should not be over- separations than at large separations and cannot be interpreted, it does suggest that at least a part of the overcome in principle other than by averaging many dependency of the standard deviation of separation on measures, which is the authors’ strategy. the separation itself is due to the propagation of the Conversely there is evidence that the uncertainty error in the calibration constants. in the estimate of separation increases with separation. There was no apparent correlation between the

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A New Visual Double Star in Gemini

This is due mainly to propagation of the variance in References the separation calibration constants over the number of Argyle, Bob, 2004, Observing and measuring visual pixels between the star centers. double stars, Springer. For both PA and separation arbitrary precision can be achieved by repeating the measurements enough Losse F. Reduc software, V4.5.1. http:// times according to the usual formula: www.astrosurf.com/hfosaf/uk/tdownload.htm where n = required sample size (number of repeats), z (visited 6th Feb. 2014). Napier-Munn T.J., Jenkinson G., 2009, "Measurement of some neglected southern multi- ple stars in Pavo", Webb Society Double Star (2) Section Circular 17, 6-12. = standard normal deviate for desired confidence level Napier-Munn T.J., Jenkinson G., 2010, "Measurement (= 1.96 for 95% confidence),  = known standard de- of some neglected southern multiple stars in Dora- viation of measurement, and m = acceptable margin of do and Pictor", Webb Society Double Star Sec- error (±). tion Circular 18, 40-43. Particular attention needs to be given to the meas- urement of the PA of close doubles. The procedure adopted by the authors delivers confidence intervals which are within the precision required for the effec- tive determination of orbits. As Reduc is essentially an astrometric program that determines PA and separation by counting pixes between identified image centers, the general conclu- sions of this paper are likely to apply to any similar measurement method.

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A New Double Star in Andromeda

T. V. Bryant III Little Tycho Observatory 703 McNeill Road, Silver Spring, Md 20910 [email protected]

Abstract: A new double star has been found in Andromeda, (0:02:01.73 +23:46:51.0, J2000). A measurement made with the Aladin tool1 of the new double gives 27.9 arc seconds of separation and a position angle of 292°. The APASS2 visual magnitudes, as reported by the UCAC43 are 9.049 and 9.735.

The pair was found during a computer search of the UCAC4 catalog, comparing all stars listed brighter than 12.0mv, with nearby stars brighter than 13.0mv and closer to the first star than 1 arc minute against listings in the Washington Double Star Catalog (WDS)4. 12mv was chosen as it is the limiting magnitude for my 20 cm SCT when observing double stars. The pair at coordi- nates 0:02:01.73 +23:46:51.0 in particular was noticed as being fairly bright with similar proper motions, and it was not listed in the WDS. The proper motion of the primary is 26.9 mas/yr in and 6.0 mas/yr in , and that of the secondary is 26.7 mas/yr in right ascension and 6.2 mas/yr in declination. The primary's UCAC4 id is 569-000097, the sec- ondary's UCAC4 id is 569-000094. The above data were generated using the Aladin Figure 1. DSS image of the Proposed new double star. Sky Atlas tool. Information about the find was communicated to William Hartkopf5, of the USNO, who suggested I re- enough to have been an easy target for the Herschels or port this find to the JDSO. He has also researched the Struves. Perhaps it was an early double that was later pair itself, and found it in the Tycho26, 2MASS7, lost, due to poor coordinates. UCAC4, WFC8, and the AC 20009 catalogs, so The pair has been provisionally entered into the "prediscovery" measures in the WDS now date back to WDS under designation 00020+2347 TVB 2. 1893. Dr. Hartkopf further adds that the pair is bright Figure 1 is a photo of the new binary from the DSS

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A New Double Star in Andromeda

as rendered by the Aladin Sky Atlas tool. References 1) Aladin web site, http://aladin.u-strasbg.fr/ 2) AAVSO APASS web site, http://www.aavso.org/ apass 3) Zacharias, et al, 2012. US Naval Observatory CCD Astrograph Catalog (UCAC4), http:// www.usno.navy.mil/USNO/astrometry/optical-IR- prod/ucac 4) Brian D. Mason, Gary L. Wycoff, William I. Hartkopf, Geoffrey G. Douglass, and Charles E. Worley, 2001. The Washington Double Star Cata- log, http://ad.usno.navy.mil/wds/ 5) William Hartkopf, Astrometry Department, U.S. Na- val Observatory 3450 Massachusetts Ave, NW, Washington, DC 20392 6) Tycho-2 web site, http://www.astro.ku.dk/~erik/ Tycho-2/ 7) 2MASS web site, http:// www.ipac.caltech.edu/2mass/ 8) WFC Explanatory paper, http:// iopscience.iop.org/1538-3881/132/1/50/ fulltext/205198.text.html 9) AC 2000 web site, http://ad.usno.navy.mil/ac/

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63 New Common Proper Motion Binaries in the LSPM-North Catalog

F. M. Rica

Astronomical Society of Mérida [email protected]

Abstract: As a continuation of the work published by Rica (2012), the discovery of 63 new high ( > 0.15 mas yr-1) common proper motion binaries selected from the LSPM-North Catalog is presented. Astrometric measures (position angles and angular distances) were performed mainly using the astrometric catalogs 2MASS. In this paper most of the new binaries are closer than in the first work.

ry component; LSPM-North Catalog identification for Introduction the primary and secondary components; V magnitude A first previous work was published by Rica (2012) for the primary and secondary components; AR and presenting the discovery of 145 new high ( > 0.15 mas DEC proper motion for the primary and secondary yr-1) common proper motion binaries selected from the components listed in LSPM-North Catalog; finally the LSPM-North Catalog (Lepine & Shara 2005). Then, a , position angle and distance for the binary meas- detailed astrophysical studied was performed. Among ured by the author. the stars in that sample, there were 5 candidates nearer The V magnitude mainly are those listed in the than 25 pc, as well as 73 subdwarfs and 9 white dwarfs LSPM-North Catalog; but often other sources or meth- unreported in the literature. Among the binaries, there ods are used: were some composed of two subdwarfs and others  The relationship of Brian D. Warner (2007) trans- composed of two white dwarfs. Others have very wide forming the 2MASS JHK photometry to V physical separations (13 binaries with s > 20,000 AU) magntiude. These values are listed in bold. This and 4 binaries are wide (s > 5,000 AU), low- (Ma relationship works fine for stars with spectral types + Mb < 0.4) binaries. earlier than K5. For red stars the J-K color does not This second work extends the first, with the discov- change as much with temperature and tends to give eries of 63 new high ( > 0.15 mas yr-1) common prop- brighter V magnitudes (even 1-2 magnitudes er motion visual binaries in the LSPM-North Catalog brighter). Astrometric measures (position angles and angular dis-  V magnitude obtained converting the SDSS pho- tances) were performed using the astrometric catalogs tometry. These values are listed in italic. 2MASS and SDSS in addition to SuperCosmos Sky  V magnitude from UCAC4 catalog, in underline Survey plates. In this work, most of the new binaries bold. are closer and the components fainter than in Rica (2012). No astrophysical study was performed; this will be carried out in a future study. The astrometric measures listed in Table 1 were Results calculated using astrometric catalogs: Table 1 lists data for the 63 new binaries presented  From 2MASS when the observational epoch ranges in this work. From the left to the right the columns are: between 1998.0 and 2001.0. AR and DEC (2000 equinox) coordinate for the prima-

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63 New Common Proper Motion Binaries in the LSPM-North Catalog

 From the SuperCosmos Sky Survey catalog (binaries with primaries J0136+4336S, J0422+3357N); epochs in italic.  From the catalog of the Sloan Digital Sky Survey (epochs in bold).

Since the common proper motion nature for the binaries presented here was detected using a catalog (that of Lepine and Shara) compiled analyzing photo- graphic plates and digital CCDs, it is necessary give visual evidence for the binary nature. In the Figures 1- 66 photographic and CCD images for the new binaries are showed. Some explation is needed:  Red circles with a line came from the SIMBAD database with AR and DEC coordinate from 2MASS. The line shows the direction of the proper motion and its magnitude for 1000 years.  For many binaries an old DSS plate is shown to- gether with a modern CCD image (from 2MASS or SDSS).  For other binaries only one RGB image is shown where the common proper motion nature is clear.

Often the common proper motion is clear when we compare the position of the stars in an old DSS plate and SIMBAD positions. For many cases the new bina- ries are very close and even 2MASS images don’t show clearly the duplicity. In theses cases SDSS images are used. Sometimes a reticle appears in the images. Both images are locked, that is, show the same portion of the sky and the reticle points to the same posicion in both images. This can help us to identify the position of the star in the first or second epoch. The new binaries listed in Table 1 should be considered for cataloguing in WDS as the binaries from FMR 176 to FMR 238.

References Brian D. Warner, 2007, MPBu, 34, 113 Lépine S., Shara M. M., 2005, AJ, 129, 1483 Rica, F. M., 2012, JDSO, 8, 260

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63 New Common Proper Motion Binaries in the LSPM-North Catalog

Table 1. New Binary stars: Positions, identifications, magntiudes, proper motions and measures

AR_2000 DEC_2000 LSPM LSPM Vmag Vmag pmRA pmDE pmRA pmDE Epoch  

Primary Primary Primary Secondary Pri. Sec. Pri. Primary Sec. Sec. (deg) (as)

00 11 51.14 +38 50 28.8 J0011+3850S J0011+3850N 14.2 15.6 0.193 -0.055 0.193 -0.055 1998.833 330.9 5.91

00 12 06.75 +47 04 10.3 J0012+4704E J0012+4704W 14.77 18.26 0.169 0.012 0.169 0.012 1998.842 290.7 9.60

00 20 49.09 +53 39 24.7 J0020+5339 J0020+5341 17.5 17.99 0.185 0.003 0.159 -0.030 1998.847 19.2 130.91

01 36 41.18 +43 36 08.9 J0136+4336S J0136+4336N 17.99 18.88 0.156 0.009 0.156 0.009 1989.755 197.8 9.56

01 41 13.50 +14 37 26.3 J0141+1437E J0141+1437W 14.84 14.92 0.105 -0.149 0.105 -0.149 2000.896 302.8 4.54

01 41 20.01 +53 35 23.4 J0141+5335W J0141+5335E 17.48 17.59 0.152 -0.077 0.152 -0.077 1998.935 50.8 3.69

01 43 23.38 +23 26 51.0 J0143+2326S J0143+2326N 19.01 19.04 0.139 -0.093 0.139 -0.093 1998.880 355.2 4.62

02 15 25.51 +67 27 24.7 J0215+6727W J0215+6727E 14.7 16.1 0.166 -0.026 0.166 -0.026 1999.861 110.3 4.37

03 28 11.40 +22 59 06.6 J0328+2259E J0328+2259W 17.82 18.11 0.010 -0.230 0.010 -0.230 1997.820 297.7 3.94

03 33 43.35 +01 08 30.0 J0333+0108S J0333+0108N 13.58 13.72 0.159 -0.116 0.159 -0.116 2000.049 338.5 3.54

03 57 39.99 +57 15 39.9 J0357+5715W J0357+5715E 17.12 18.13 -0.063 -0.151 -0.063 -0.151 1999.033 107.5 8.25

04 06 51.17 +16 15 36.7 J0406+1615W J0406+1615E 16.43 20.3 0.105 -0.153 0.105 -0.153 2000.905 87.6 6.66

04 22 37.12 +33 57 46.3 J0422+3357N J0422+3357S 14.63 18.31 0.112 -0.120 0.112 -0.120 1993.801 150.0 12.31

04 23 38.72 +34 04 34.6 J0423+3404N J0423+3404S 14.2 14.27 0.160 -0.014 0.160 -0.014 1997.957 26.0 6.59

04 32 59.94 +22 44 23.7 J0432+2244W J0432+2244E 16.6 17.0 0.092 -0.143 0.092 -0.143 2000.741 92.4 4.71

04 32 25.59 +34 56 03.0 J0432+3456S J0432+3456N 14.86 15.5 0.148 0.139 0.148 0.139 1998.074 347.2 4.38

04 40 34.42 +61 02 32.3 J0440+6102W J0440+6102E 11.9 12.28 0.142 -0.261 0.142 -0.261 2000.156 51.3 3.89

04 50 10.00 +14 46 10.7 J0450+1446W J0450+1446E 12.98 15.5 0.190 -0.094 0.190 -0.094 1997.774 90.7 4.35

05 15 46.64 +30 00 50.8 J0515+3000S J0515+3000N 16.3 17.4 -0.013 -0.163 -0.013 -0.163 1998.088 340.5 4.37

05 16 59.97 +16 23 32.5 J0516+1623S J0516+1623N 16.91 17.27 0.023 -0.174 0.023 -0.174 1997.779 348.1 4.49

05 34 44.43 +14 52 59.6 J0534+1452W J0534+1452E 17.44 18.57 0.109 -0.125 0.109 -0.125 1998.736 113.4 6.15

06 17 21.24 +09 52 53.1 J0617+0952E J0617+0952W 9.93 16.76 -0.039 -0.150 -0.079 -0.127 1999.738 270.5 164.34

06 32 19.90 +27 45 29.9 J0632+2745W J0632+2745E 18.28 19.12 -0.122 -0.094 -0.122 -0.094 2006.887 85.0 2.14

06 49 40.60 +03 22 35.0 J0649+0322E J0649+0322W 13.17 15.16 0.026 -0.185 0.026 -0.185 1999.877 243.7 4.47

07 03 23.38 +01 32 20.2 J0703+0132W J0703+0132E 14.78 16.9 0.132 -0.127 0.132 -0.127 1999.927 46.8 5.63

07 53 32.43 +11 08 49.6 J0753+1108N J0753+1108S 15.31 15.37 0.089 -0.161 0.089 -0.161 2000.903 175.1 3.60

08 01 33.39 +36 18 13.5 J0801+3618S J0801+3618N 17.61 17.98 -0.070 -0.154 -0.070 -0.154 2001.145 42.7 4.36

08 05 42.28 +11 36 26.2 J0805+1136W J0805+1136E 15.46 16.5 0.010 -0.164 0.010 -0.164 2000.116 111.0 3.89

08 13 37.54 +15 27 15.0 J0813+1527 J0813+1528 12.16 18.44 -0.152 -0.017 -0.155 -0.017 1997.840 295.8 148.02

08 17 50.05 +50 07 41.5 J0817+5007S J0817+5007N 10.73 14.55 -0.040 -0.238 -0.040 -0.238 1999.799 17.7 4.15

08 18 02.27 +05 31 55.9 J0818+0531S J0818+0531N 13.08 15.1 0.044 -0.165 0.044 -0.165 2000.074 42.0 4.32

08 42 59.88 +83 44 47.4 J0842+8344 J0843+8344 17.77 18.79 -0.009 -0.160 -0.009 -0.160 2006.229 88.5 2.99 08 45 22.77 +26 01 32.8 J0845+2601E J0845+2601W 12.08 12.61 0.138 -0.189 0.138 -0.189 1998.091 269.7 4.24

Table 1 concludes on next page.

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63 New Common Proper Motion Binaries in the LSPM-North Catalog

Table 1 (conclusion). New Binary stars: Positions, identifications, magntiudes, proper motions and measures

AR_2000 DEC_2000 LSPM LSPM Vmag Vmag pmRA pmDE pmRA pmDE Epoch  

Primary Primary Primary Secondary Pri. Sec. Pri. Primary Sec. Sec. (deg) (as)

09 19 51.27 +41 40 38.3 J0919+4140N J0919+4140S 14.6 17.29 -0.133 -0.092 -0.133 -0.092 1999.927 193.2 4.49

09 33 38.87 +00 49 32.0 J0933+0049S J0933+0049N 13.72 15.32 -0.176 0.031 -0.176 0.031 2000.916 41.9 3.18

09 41 11.79 +33 15 13.0 J0941+3315N J0941+3315S 16.7 17.47 0.257 -0.360 0.257 -0.360 1999.971 164.1 7.33

09 46 13.39 +00 21 10.0 J0946+0021N J0946+0021S 19.5 19.78 -0.162 -0.042 -0.162 -0.042 2000.075 153.3 4.02

10 13 27.70 +28 39 05.7 J1013+2839W J1013+2839E 15.53 16.45 -0.133 0.128 -0.133 0.128 1998.916 45.8 3.45

10 15 43.90 +17 05 13.0 J1015+1705N J1015+1705S 17.53 19.69 -0.137 -0.111 -0.137 -0.111 1997.922 27.4 5.61 +20 01 10 24 46.32 J1024+2001E J1024+2001W 17.0 17.0 -0.050 -0.158 -0.050 -0.158 2005.194 264.0 2.46 41.2 10 25 08.77 +00 44 08.3 J1025+0044E J1025+0044W 16.86 19.2 0.066 -0.141 0.066 -0.141 1999.220 249.6 2.54

10 51 47.75 +02 53 40.2 J1051+0253S J1051+0253N 17.78 18.02 -0.343 -0.063 -0.343 -0.063 2000.116 33.1 3.53

11 04 32.74 +41 40 40.6 J1104+4140N J1104+4140S 10.95 --- -0.154 -0.177 -0.137 -0.163 1999.862 141.9 3.49

11 21 33.39 +12 30 59.1 J1121+1230W J1121+1230E 17.82 18.52 -0.235 -0.379 -0.235 -0.379 1998.900 112.1 3.59

11 26 38.89 +35 50 45.2 J1126+3550W J1126+3550E 16.82 17.61 -0.169 -0.031 -0.169 -0.031 2004.206 31.6 3.23

11 32 17.01 +17 53 36.4 J1132+1753N J1132+1753S 12.73 17.45 0.072 -0.143 0.072 -0.143 1999.340 151.3 6.15

11 35 57.64 +75 32 48.9 J1135+7532N J1135+7532S 14.95 16.46 -0.187 -0.085 -0.187 -0.085 2006.328 90.3 398.98

12 01 59.81 +09 34 43.8 J1201+0934E J1201+0934W 9.79 14.5 -0.163 -0.076 -0.158 -0.073 2000.200 226.0 5.66 +05 20 12 24 00.71 J1224+0520W J1224+0520E 16.2 16.53 -0.056 -0.264 -0.056 -0.264 2007.047 107.0 2.95 51.7 14 27 54.41 +13 20 14.6 J1427+1320W J1427+1320E 16.5 16.7 -0.207 -0.081 -0.207 -0.081 1999.133 91.7 3.91

15 11 54.87 +03 46 51.8 J1511+0346 J1511+0349 11.29 11.69 0.095 -0.136 -0.034 -0.164 2000.280 9.4 139.71

15 44 54.00 +09 04 57.8 J1544+0904 J1544+0905 15.12 17.14 -0.189 -0.122 -0.189 -0.122 2000.362 23.9 3.70

16 44 01.12 +44 41 51.9 J1644+4441 J1643+4438 13.7 19.26 0.041 -0.204 0.041 -0.204 2001.225 188.7 178.02

16 52 18.84 +03 13 14.0 J1652+0313N J1652+0313S 14.32 17.0 0.076 -0.152 0.076 -0.152 2000.442 147.6 7.14

17 08 23.73 +28 49 32.2 J1708+2849E J1708+2849W 14.59 16.98 -0.141 0.090 -0.141 0.090 1999.425 250.2 3.41

18 36 30.06 +19 30 49.0 J1836+1930W J1836+1930E 14.3 19.46 -0.158 -0.006 -0.158 -0.006 1998.464 86.0 15.06

20 57 04.31 +25 20 38.5 J2057+2520N J2057+2520S 13.34 14.63 0.020 -0.194 0.020 -0.194 1997.803 137.7 3.55

21 09 59.52 +49 07 49.8 J2109+4907E J2109+4907W 12.34 15.1 0.151 0.027 0.151 0.027 2000.448 254.7 8.68

21 14 42.24 +53 44 48.4 J2114+5344S J2114+5344N 15.00 15.13 0.135 0.075 0.135 0.075 2006.394 290.5 2.51

21 24 50.81 +18 03 41.2 J2124+1803E J2124+1803W 15.84 17.8 0.146 -0.055 0.146 -0.055 1999.863 286.8 7.94

22 22 23.60 +44 10 28.6 J2222+4410 J2222+4411 11.03 19.11 0.104 0.106 0.103 0.117 1998.776 296.6 168.89

23 29 46.36 +07 36 38.1 J2329+0736N J2329+0736S 16.62 17.97 0.134 -0.085 0.134 -0.085 2005.734 270.1 3.10

23 45 09.95 +05 19 46.9 J2345+0519S J2345+0519N 15.42 17.09 -0.079 -0.144 -0.079 -0.144 2008.816 342.6 3.35

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63 New Common Proper Motion Binaries in the LSPM-North Catalog

Figure 3. Binary with primary J0020+5339 (at the bottom of the image and secondary J0020+5341 (at the top). RGB image composed by DSS plates.

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63 New Common Proper Motion Binaries in the LSPM-North Catalog

Figure 14. Binary with primary J0423+3404S. Simbad plots an erroneous size for the symbol. The brightest component (from blue to infrared band) is the northern star.

Figure 16. Binary with primary J0432+3456S. Right: 2MASS image where we can see a pear- shaped binary. Left: DSS RGB image where we can see the motion of this pear-shaped binary in two very different epochs (blue and red).

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63 New Common Proper Motion Binaries in the LSPM-North Catalog

Figure 17. (Above) Binary with primary J0440+6102W. Figure 18. (Right) Binary with primary J0450+1446W.

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63 New Common Proper Motion Binaries in the LSPM-North Catalog

Figure 29. (Left) Binary with primary J0813+1527. RGB image of DSS plates. The secondary star is weak and appears as a pair of blue and red points (marked with arrows). Figure 30. (Above) Binary with primary J0817+5007S

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63 New Common Proper Motion Binaries in the LSPM-North Catalog

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63 New Common Proper Motion Binaries in the LSPM-North Catalog

Figure 40. Binary with primary J1024+2001E. (Left) DSS plate where the binary is observed as an elliptical object slight north of the Simbad position. (Right) SDSS image where the binary is split into compo- nents with East-West orientation.

Figure 42. Binary with primary J1025+0044E. The secondary compo- nent is not visible in the DSS image (left).

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63 New Common Proper Motion Binaries in the LSPM-North Catalog

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63 New Common Proper Motion Binaries in the LSPM-North Catalog

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Double Star Measures Using the Video Drift Method - IV

Richard L. Nugent International Occultation Timing Association Houston, Texas [email protected]

Ernest W. Iverson International Occultation Timing Association Lufkin, Texas [email protected]

Abstract: Position angles and separations for 240 multiple star systems are presented using the video drift method. The drift method generates a Cartesian (x,y) coordinate pair for the primary and companion star for each video frame during the drift. Position angle and separation are cal- culated from these coordinates. Most doubles had multiple drifts observed over several nights resulting in 1,000’s of (x,y) pairs analyzed per system. Several systems lacked measurements since the early 1900’s or had less than 10 measurements since their discovery. The video drift method provides high systematic accuracy.

significant advantage of this method is that data collec- Introduction tion and subsequent data analysis is almost completely In our first paper, Nugent and Iverson 2011, and automated with little human interaction. Since the subsequent papers, Nugent and Iverson 2012 and method does not rely on visual measurements, it is not Nugent and Iverson 2013, (hereinafter called Papers I, plagued by personal bias/personal error, or optical axis II, and III) we described a new video method that com- problems with eyepieces. This includes aberrations and putes both the position angle and separation for a dou- distortions from the edge to the center of the field of ble star. A short video clip of the multiple star system view found in some eyepieces and the misalignment of drifting across the field of view is used by the freeware eyepieces with the optical axis of the telescope. program Limovie (Miyashita, 2006) to capture 100’s to Unlike other video/CCD methods, no calibration 1,000's of (x,y) positions for each component. Although doubles are needed to determine plate scale, no line is Limovie was originally written to measure the change drawn to determine the east-west direction, no star cata- in light levels during an occultation, it also produces a log is needed since no “plate adjustment” is performed, table of Cartesian (x,y) coordinates for both compo- and no video frames are discarded. Each double star nents along with the brightness levels for each video drift is self calibrating (see discussion below on pre- frame. VidPro, an Excel program written by co-author calibration). The VidPro program computes a unique RLN, reads the (x,y) coordinate data and computes a scale factor, an offset from the east- west direction simultaneous solution for the position angle, separation compared to the camera's pixel array, and standard de- and other statistical quantities for each double star sys- viations for both position angle and separation for each tem. drift. The offset of the pixel array alignment of the vid- Paper I outlined the theory behind the video drift eo camera’s chip from the true east-west direction (drift method and compared the results to several doubles that angle) is calculated using the method of least squares to had no change in PA and separation for 120+ years. A

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Double Star Measures Using the Video Drift Method - IV

an accuracy of better than 0.02°. Paper II provided the cording methods used by the authors (all recording formulas for determining a unique PA and separation methods will have these issues) skew the video format from a simultaneous solution of all the (x,y) pairs ob- slightly as part of the compression scheme before copy- tained from all the video drift runs made for a particular ing the video into the storage medium. As a result, the double star system. field of view (image aspect ratio) is not a perfect match of the sky but slightly distorted. Methodology To compensate for this we calibrated each record- Preference was given to multiple star systems ing system by adjusting the image aspect ratio until it where the WDS lacked measurements for at least the matched the real sky. This was done forcing Limovie past 10 years and had less than 10 previous measure- to open each video using an Avisynth video editor ments. This criterion applies to many of the multiple script (Rudiak-Gould, 2008) containing the filter star systems measured at the epoch of their measure- "LanczosResize". Several long term stable WDS dou- ment. In some cases, where one component of a com- bles (as verified by requesting the full observational plex system meets this requirement, all of the other catalog entry from the USNO) and from PA/Sep deter- components were also measured for completeness even mined directly from RA, DEC coordinates in recent star though they had been well measured in the past. Eleven catalogs from the VisieR database were used to deter- systems lacked measurement since 1899-1933. The mine the correct aspect ratio. faintest system measured had primary/secondary mag- To do this we picked a convenient, standard video nitudes of +13.2, +14.4. aspect ratio size of 640x480 pixels. Holding the hori- Calibration zontal scale (640 pixels) constant, we then varied the vertical scale to match the sky. Once determined, the During the preparation of our previous papers aspect ratio was adjusted slightly by trial and error to (Papers I, II, and III) we noticed that the measured val- give the best average data reduction performance. For ues of some widely separated doubles often had notice- our 14" SCT’s the size that closely matched the sky was able deviations from the WDS catalog value. If the 640x510 for Nugent’s system and 640x465 for Iver- deviation seemed unusual we held back that measure- son’s system. This calibration procedure only needs to ment pending further investigation and additional meas- be done once, and is valid until the hardware in the vid- urements. These differences were typically not noticea- eo path changes. ble for double stars with separations less than 100 arc A common practice is to check the accuracy of new seconds. measurements by comparing them to the WDS sum- This issue lies largely with the recording system’s mary catalog value. Unfortunately this is not a valid storage/compression method into a memory card or to a test of accuracy. The published WDS value is just the computer’s hard drive. The telescope camera system most recent value entered into the catalog. Although also introduces small optical effects (aberrations, distor- these measurements are typically very good, it should tions, gnomonic projection) into the field of view rec- be pointed out that the last entry can have a significant orded. However, for determining relative positions be- error associated with it. False assumptions about the tween two stars and the small field of view associated accuracy of a new measurement can also occur when with double stars these optical effects can generally be the last catalog entry is several years old or the double ignored. star is undergoing rapid change. Author Nugent uses a digital video recorder (DVR) The telescope equipment used and scale factors are that stores videos onto a memory card. Author Iverson summarized in Table 1. Results of the measurements uses an analog 8mm video tape recorder that exports made using the video drift method are given in Table 2. the video via a fire wire port into a computer. The re- (Continued on page 222)

Table 1. Telescopes used in this research. Scale factors vary slightly due to the declination of the doubles.

Telescope Aperture Focal Length Scale Factor

Meade LX-200 14” (35 cm) 3350mm f/10 0.6”/pixel

Questar 3.5” (9 cm) 1299mm f/14.4 1.6”/pixel

Celestron Refractor 6” (15.2 cm) 1220mm f/8 1.4”/pixel (barlow)

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Double Star Measures Using the Video Drift Method - IV

Table 2. Results of 240 double stars using the video drift method.

# x-y WDS Discoverer PA° σ-PA Sep" σ-Sep Date Mag Pri Mag Sec Drifts Nights pairs 00024+1047 BGH 1AB,C 300.6 0.1 63.2 0.1 2012.753 3653 8.80 8.55 6 2 00030+0723 HJ 3233AC 324.6 0.3 82.9 0.6 2014.008 1148 10.70 10.2 2 1 00031+0816 STF3054 181.5 0.2 33.5 0.1 2012.751 4226 8.13 9.05 6 2 00052+3020 STF3058 52.2 0.7 12.6 0.1 2012.858 2386 7.81 9.21 3 1 00150+0849 STF 12 147.0 0.6 11.3 0.1 2012.751 4180 6.06 7.51 6 2 00176+1300 HJ 3 262.1 0.6 12.1 0.1 2012.753 4201 9.97 10.24 6 2 00180+0931 AG 1 210.9 0.6 11.8 0.1 2012.753 4237 9.21 10.07 6 2 00239+2930 STF 28AB 224.3 0.2 32.9 0.1 2012.863 4452 8.32 8.55 6 2 00320+2831 S 386 17.7 0.2 43.1 0.1 2012.863 4618 8.92 8.94 6 2 00399+2126 STF 46 198.0 1.7 6.3 0.2 2012.841 2110 5.56 8.49 3 1 00477+1253 STTA 8AB 125.1 0.2 44.3 0.1 2012.753 3919 8.97 9.25 6 2 00499+3027 STTA 9AB 244.3 0.1 116.9 0.1 2012.863 3369 7.75 8.81 6 2 00531+6107 BU 497AB 169.6 0.1 144.6 0.1 2012.841 3655 4.85 9.79 3 1 00546+3910 STF 72 173.8 0.7 22.7 0.2 2012.863 2698 8.38 9.31 3 1 00556+3433 HJ 629AC 256.8 0.1 66.2 0.1 2012.863 4235 9.32 8.86 6 2 01438+5553 STT 35 92.1 0.8 14.4 0.1 2012.841 3379 6.98 10.81 3 1 01581+4123 S 404AB 82.7 0.5 28.9 0.2 2012.863 2569 7.64 9.74 3 1 01596+6437 HJ 1100 309.1 0.3 43.1 0.1 2012.841 4181 5.28 11.99 3 1 02103+3322 STF 219 184.6 1.0 11.4 0.2 2012.863 2499 8.03 8.89 3 1 02135-2546 HJ 2120 259.1 0.9 49.5 0.7 2014.008 1258 10.26 10.53 2 1 02157+1046 STF 237AB 237.2 0.9 14.5 0.2 2014.008 1300 9.54 9.94 2 1 02157+1046 STF 237AC 275.0 0.5 72.7 0.5 2014.008 972 9.54 11.87 1 1 02157+1046 HJL1014AE 4.9 0.2 167.4 0.5 2014.008 1263 9.54 10.81 2 1 02157+1046 HJL1013BE 8.7 0.1 176.6 0.5 2014.008 1280 9.94 10.81 2 1 02166-0516 A 445AC 131.5 0.7 69.1 0.9 2014.008 1111 9.95 11.31 2 1 02180+1958 GWP 294 7.2 0.9 74.9 0.9 2014.008 1372 11.2 11.4 2 1 02187+3429 STF 246 122.4 1.3 9.6 0.2 2012.863 2510 7.82 9.26 3 1 02371-1112 TOK 232AB 233.8 0.1 187.3 0.3 2014.019 907 8.11 11.84 2 1 02383+3744 BU 305AC 205.5 0.6 19.4 0.1 2013.882 1844 6.16 11.37 2 1 02383+3744 WAL 18AD 78.1 0.4 48.7 0.3 2013.882 1637 6.16 12.13 2 1 02389-2810 HJ 3518AB 15.8 1.1 13.3 0.3 2014.019 1683 9.38 11.20 2 1 02389-2810 HJ 3518AC 199.6 0.6 30.7 0.3 2014.019 1654 9.38 11.6 2 1 02407+2704 STF 289 0.3 0.3 28.4 0.2 2012.841 2239 5.30 9.56 3 1 02438-2754 BU 261AC 133.3 0.3 68.7 0.3 2014.019 1467 7.86 10.51 2 1 02439-2758 HDO 60 164.4 1.6 8.7 0.3 2014.019 1684 10.31 12.1 2 1 02501-0616 J 1453AB 200.8 1.7 9.2 0.3 2014.022 1499 11.1 10.7 2 1 02501-0616 J 1453AC 68.7 0.6 38.5 0.4 2014.022 1389 11.1 13.0 2 1 02508-1212 UC 826 163.5 0.7 28.7 0.4 2014.022 1517 11.8 12.9 2 1 02519+2835 AZC 27 16.4 0.9 27.5 0.4 2014.022 1685 11.3 14.0 2 1 02524-1546 LDS5398 105.0 0.3 114.8 0.6 2014.022 1103 12.8 13.94 2 1 02532-1007 GWP 385 22.2 0.7 31.3 0.3 2014.022 1471 10.5 12.4 2 1 02537-1421 GAL 80 154.7 3.1 5.6 0.4 2014.022 1537 11.18 11.87 2 1 02539-3220 PRO 11 168.2 1.9 6.5 0.2 2014.019 1770 10.15 11.68 2 1 02558-1606 GWP 398 56.2 0.3 81.4 0.4 2014.022 1274 12.0 13.8 2 1

Table 2 continues on next page.

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Double Star Measures Using the Video Drift Method - IV

Table 2 (continued). Results of 240 double stars using the video drift method.

# x-y WDS Discoverer PA° σ-PA Sep" σ-Sep Date Mag Pri Mag Sec Drifts Nights pairs 02560-1607 ARA 16 232.9 2.8 7.9 0.4 2014.022 1535 13.1 13.4 2 1 02565+0039 BAL 960 215.5 2.6 8.6 0.4 2014.005 1483 12.57 12.57 2 1 02577-2858 HJ 3543AB 266.1 2.2 9.1 0.5 2014.022 1648 10.5 10.9 2 1 02577-2858 HJ 3543AC 65.0 1.8 17.1 0.4 2014.022 1617 10.5 12.3 2 1 02577-2858 ABH 17AD 263.6 0.4 84.8 0.6 2014.022 1296 10.5 13.7 2 1 03074+1753 HJL1020 358.8 0.3 104.2 0.6 2014.008 1348 6.10 10.42 2 1 03079-2813 LDS 86AB 208.3 0.4 66.3 0.5 2014.019 1556 10.45 12.63 2 1 03079-2813 HDS3408AC 96.3 0.6 37.4 0.4 2014.019 1525 10.45 11.68 2 1 03088+2339 POU 247 139.3 1.7 13.4 0.4 2014.019 1604 11.94 12.0 2 1 03093+2046 HJL1021 239.3 0.2 122.2 0.4 2014.008 1464 6.54 8.77 2 1 03107-2007 CBL 120 312.9 0.7 59.0 0.7 2014.008 1213 7.6 10.5 2 1 03125-3449 LDS 89 329.4 0.6 52.8 0.5 2014.019 1706 10.59 13.2 2 1 03163-2010 ARA 834 203.4 2.2 9.2 0.3 2014.022 1587 10.7 12.0 2 1 03168-1956 HJ 3561 152.2 1.0 25.7 0.4 2014.022 1548 10.10 13.9 2 1 03180-1744 ARA 321 67.4 3.2 8.0 0.5 2014.022 1524 13.0 13.0 2 1 03184-2734 BVD 33 301.0 0.7 24.6 0.3 2014.019 1610 10.33 11.18 2 1 03195-2815 UC 981 248.3 1.4 20.4 0.5 2014.019 1628 13.2 14.4 2 1 03207+1736 HJ 3246AB 193.6 0.2 158.7 0.6 2014.008 623 9.96 11.35 1 1 03220-3349 BVD 35 239.6 1.2 18.1 0.3 2014.019 1749 11.47 11.64 2 1 03222-0020 UC 993 304.6 0.6 45.0 0.5 2014.022 1359 10.8 13.6 2 1 03227-2258 UC 996 130.4 1.0 15.0 0.3 2014.022 1576 9.8 14.4 2 1 03234-2253 ARA1975 246.6 2.3 10.8 0.4 2014.022 1588 12.26 13.4 2 1 03240-2613 HJ 3572 94.4 1.5 20.8 0.6 2014.008 1368 8.24 8.53 2 1 03247-2131 HJ 3574 85.8 2.2 16.4 0.9 2014.022 727 11.76 14.4 1 1 03263-3057 LDS5426 36.2 0.8 32.1 0.4 2014.019 1661 11.83 13.7 2 1 03277-3215 HJ 3578 41.2 0.7 29.5 0.3 2014.019 1698 9.2 12.6 2 1 03282-1335 GAL 330 81.8 2.1 9.5 0.4 2014.019 1513 11.63 12.6 2 1 03305-1752 B 2517AB 176.1 1.2 25.1 0.6 2014.022 1568 9.74 12.9 2 1 03323-0705 STF 411AB 87.9 0.7 18.8 0.2 2014.019 1434 7.36 9.19 2 1 03323-0705 STF 411AC 31.4 0.4 44.2 0.3 2014.019 1354 7.36 11.2 2 1 03336-0725 CLL 2 138.9 0.2 66.3 0.3 2014.019 1317 7.61 7.96 2 1 03344-1940 GWP 480 1.3 0.7 36.2 0.7 2014.022 1564 12.2 13.6 2 1 03346-1613 GAL 332 235.2 1.0 20.9 0.4 2014.022 1506 10.68 11.99 2 1 03363-1020 UC 1032 84.5 1.1 29.1 0.6 2014.022 696 12.2 13.1 1 1 03459+2433 HJL1026AB 129.8 0.2 149.7 0.4 2013.121 5382 5.75 6.42 3 1 03484-2025 HJ 3594 114.2 1.1 9.7 0.3 2014.005 1545 9.1 14.5 2 1 03556+2419 POU 318 335.2 2.6 7.5 0.3 2014.005 1623 11.83 12.6 2 1 04072-3118 RSS 70 2.0 1.1 13.1 0.2 2014.019 1729 10.22 13.0 2 1 04157-3033 B 2568A,BC 219.2 0.3 105.1 0.7 2014.019 1421 8.93 13.74 2 1 04297-1043 GAL 134 210.6 1.5 14.3 0.4 2014.022 1479 9.77 12.3 2 1 04368-1736 ARA 154 304.5 3.2 5.0 0.4 2014.005 1554 11.98 14.4 2 1 04429+1843 LDS2266AB 102.8 0.1 142.3 0.3 2013.038 1853 7.18 10.20 4 1 04543+0722 STF 612AC 264.2 0.5 59.8 0.5 2014.005 1231 8.33 14.1 2 1 05210+3805 SEI 202 114.5 2.2 7.6 0.2 2013.199 2789 10.5 11.0 3 1

Table 2 continues on next page.

Vol. 10 No. 3 July 1, 2014 Journal of Double Star Observations Page 218

Double Star Measures Using the Video Drift Method - IV

Table 2 (continued). Results of 240 double stars using the video drift method. # x-y WDS Discoverer PA° σ-PA Sep" σ-Sep Date Mag Pri Mag Sec Drifts Nights pairs 05246+0149 S 479AB 220.6 0.9 46.2 0.8 2013.121 5132 8.30 8.94 3 1 05246+0149 S 479AC 36.3 0.2 157.5 0.5 2013.121 5003 8.30 4.84 3 1 05252-1119 STF 710AB 196.2 0.9 10.2 0.3 2013.200 3725 8.61 8.91 5 1 05309+0137 BAL1294AB 52.5 1.9 8.9 0.3 2013.036 718 8.79 10.69 1 1 05322+1703 STF 730 140.8 1.7 9.6 0.3 2013.121 3315 6.06 6.44 3 1 05353-0520 HJ 1157EF 305.8 3.7 8.5 0.6 2014.005 1232 12.8 12.8 2 1 05382+2429 POU 764 54.3 2.3 21.0 0.8 2014.005 1565 12.02 12.2 2 1 05404-2151 ARA1278 322.0 2.2 9.1 0.4 2014.005 1539 12.08 12.4 2 1 05410+3913 ALI1057 312.4 1.8 13.7 0.3 2014.005 1891 11.47 11.8 2 1 05429+0001 STF 782AB 305.3 0.2 47.1 0.1 2012.956 3718 8.60 8.83 6 2 05485-1322 STF 801A-BC 327.5 0.6 26.8 0.4 2013.037 2035 7.49 10.1 3 1 05506-0126 STF 809AC 91.3 0.3 24.3 0.1 2012.956 3865 8.08 9.15 6 2 05575+0024 BU 1189AB,C 194.8 0.1 55.4 0.1 2012.956 3943 8.01 8.32 6 2 06116-0046 STF 871 306.4 1.0 7.2 0.1 2012.956 3906 8.84 9.38 6 2 06137-0019 BAL 686 5.9 0.7 10.1 0.1 2012.956 4132 8.83 10.51 6 2 06212+2108 S 513AB 258.5 0.1 59.2 0.1 2013.049 3787 7.31 8.92 6 2 06267+0027 STF 910A,BC 151.5 0.1 66.0 0.2 2012.956 3782 6.99 8.11 6 2 06278+2047 SHJ 70AB 202.3 0.3 24.6 0.1 2013.121 4389 6.65 8.18 6 2 06290+2013 STTA 77AB 329.8 0.1 111.3 0.2 2013.159 3692 4.10 8.01 6 2 06321+0130 BAL1315 139.9 0.6 12.7 0.1 2012.956 4076 9.89 10.45 6 2 06478-1143 STF 970 128.4 0.4 20.1 0.1 2013.066 4107 9.11 9.67 6 2 06585-1126 STF1004 90.9 0.2 20.3 0.2 2013.066 2023 8.06 9.65 3 1 06594+2514 STF1000AB,C 67.7 0.3 22.2 0.1 2013.121 4388 8.09 9.02 6 2 07027+2249 POU2324 47.8 4.6 15.4 1.2 2013.200 773 14.3 15.6 1 1 07146-1018 STF1052 21.8 0.4 19.8 0.1 2013.066 4189 8.76 9.19 6 2 07201+2159 STF1066 229.9 1.3 5.6 0.1 2013.195 1228 3.55 8.18 3 1 07287+2439 STTA 85AB 20.0 0.1 64.0 0.1 2013.121 4276 7.65 8.95 6 2 07320-0841 STF1111 221.4 0.4 19.6 0.2 2013.066 4128 8.87 9.19 6 2 07410+2148 STF1124AB 325.8 0.4 19.2 0.1 2013.049 4425 9.11 9.28 6 2 07534+2050 HJ 432AB 277.0 0.5 14.9 0.1 2013.049 4355 9.86 9.98 6 2 07549+0039 BAL1122 89.1 1.5 10.7 0.5 2013.255 2184 10.8 10.9 3 1 08086-0259 STF1190AC 246.1 0.2 64.5 0.2 2013.159 1659 4.46 9.68 3 1 08102+2551 BUP 111AB 49.0 0.2 80.0 0.2 2013.159 1865 6.58 9.32 3 1 08122+1739 STF1196AB,C 67.7 1.7 6.1 0.2 2013.159 2833 4.92 5.85 4 1 08142+1741 H 6 78AC 299.8 0.2 62.8 0.2 2013.121 3716 6.40 9.2 6 2 08142+1741 STU 22AB,D 322.9 0.1 228.6 0.2 2013.123 2499 6.51 8.94 6 2 08202+0953 CHE 112AB 50.1 0.2 34.3 0.1 2013.159 3844 9.52 10.38 6 2 08230+0738 STF1219 82.5 0.6 12.2 0.1 2013.121 4075 9.24 9.26 6 2 08358+0637 STF1245AC 110.0 0.2 99.5 0.2 2013.121 1496 5.98 10.70 3 1 08358+0637 STF1245AE 206.6 0.1 113.4 0.2 2013.123 1767 5.98 9.60 3 1 08359+0955 STF1246 115.8 0.7 10.5 0.1 2013.159 4030 8.73 9.85 6 2 08362+1347 STTA 94 132.8 0.2 43.1 0.1 2013.159 3857 7.39 8.11 6 2

Table 2 continues on next page.

Vol. 10 No. 3 July 1, 2014 Journal of Double Star Observations Page 219

Double Star Measures Using the Video Drift Method - IV

Table 2 (continued). Results of 240 double stars using the video drift method. # x-y WDS Discoverer PA° σ-PA Sep" σ-Sep Date Mag Pri Mag Sec Drifts Nights pairs 08379-0648 HJ 99AB 175.2 0.2 60.5 0.2 2013.066 4147 6.82 8.27 6 2 08401+2000 ENG 37AD 111.0 0.1 134.9 0.3 2013.195 1316 6.47 8.79 2 1 08401+2000 ENG 37AB 151.6 0.1 148.9 0.3 2013.200 1643 6.47 6.58 2 1 08401+2000 ENG 37AC 309.3 0.2 134.2 0.4 2013.200 410 6.47 9.03 1 1 08441+1357 HEI 145A,BC 130.1 0.8 9.1 0.1 2013.159 4109 10.77 10.9 6 2 08453+1316 HJ 105 255.7 0.3 25.9 0.1 2013.159 3934 9.69 10.27 6 2 08472+1110 STF1276AB 353.5 0.6 12.4 0.1 2013.159 4116 8.32 8.56 6 2 09003+0332 HJ 2479 324.6 1.2 23.1 0.5 2011.104 1397 8.99 12.35 2 1 09018+2754 SHJ 101 330.0 0.2 109.6 0.4 2011.203 683 6.08 9.22 1 1 09185-2249 ARA1764 193.0 2.7 7.1 0.3 2013.260 1628 11.19 12.3 2 1 09233+0330 STF1347 311.5 0.3 21.1 0.1 2013.121 4000 7.33 8.26 6 2 09359+1423 H 5 58 80.3 0.3 41.1 0.2 2013.159 1866 6.31 9.39 3 1 10072+0117 BAL1436 229.0 3.1 11.0 0.6 2011.203 578 10.53 12.2 1 1 10232+0542 SHJ 115AB 13.3 0.2 63.7 0.3 2013.159 1939 6.57 10.45 3 1 10262+0356 BU 1280AB 190.6 0.1 115.5 0.1 2012.041 5780 6.68 9.43 9 3 10358+0233 STF1452A,BC 327.7 0.7 10.4 0.1 2013.123 4104 9.59 9.81 6 2 10383+0115 STF1456 45.4 0.5 13.6 0.1 2013.123 4041 8.24 9.75 6 2 10416-0016 STF1464AC 226.2 0.1 66.4 0.1 2013.123 3638 8.26 10.51 6 2 10457-0130 FIL 26 260.1 0.3 20.6 0.1 2013.123 3917 10.02 10.19 6 2 11075+2203 HDS1586 201.9 1.4 13.7 0.3 2013.258 1420 8.30 11.43 2 1 13176-1157 CBL 147 344.5 1.0 24.1 0.4 2013.359 1377 11.0 12.7 2 1 13190-2637 UPT 2 21.1 1.2 17.1 0.3 2013.359 1501 10.10 10.30 2 1 13229-1854 J 1585 51.7 3.1 5.9 0.3 2013.359 1416 10.70 11.3 2 1 13324-1240 SHJ 165 78.3 0.2 48.1 0.1 2013.458 3633 7.60 8.58 6 2 13343-0019 STF1757AC 135.3 0.4 56.3 0.4 2013.351 1194 7.82 11.7 2 1 13345-1326 S 650 125.5 0.1 56.9 0.1 2013.458 3610 8.24 9.04 6 2 13408-2815 HJ 4604AC 279.4 1.2 15.8 0.3 2013.359 1498 8.08 10.44 2 1 13433-2458 HJ 2671AB 66.8 0.7 27.4 0.4 2013.359 1402 8.90 9.81 2 1 14237-2622 B 2768AB 53.9 0.2 152.9 0.5 2013.529 1136 8.81 11.31 2 1 14237-2622 B 2768BC 137.3 2.8 7.7 0.4 2013.521 1467 11.31 11.5 2 1 14242+0549 HJL1086 273.6 0.1 158.9 0.3 2013.359 1108 5.11 7.32 3 1 14265+1914 HJL1087 253.9 0.1 224.4 0.3 2013.359 808 5.43 8.38 3 1 15275-1058 STF1939 130.4 1.1 9.5 0.2 2013.458 2048 8.22 9.32 3 1 15420-1108 STF1966 52.3 0.3 23.0 0.1 2013.458 3987 9.26 9.40 6 2 15568-4058 WFC 171 349.1 1.9 9.5 0.3 2011.507 2950 12.12 12.5 3 1 16054-1948 H 3 7AC 19.7 2.6 13.6 0.7 2012.553 1208 2.59 4.52 1 1 16120-1928 H 5 6AC 336.3 0.9 41.1 0.6 2012.553 2354 4.35 6.60 2 1 16143-1025 STF2019AB,C 152.6 0.4 22.5 0.2 2013.458 4046 7.38 9.84 6 2 16305-1433 STF3104AB 228.7 1.0 9.5 0.2 2013.449 1403 9.15 10.37 3 1 16305-1433 STF3104AC 82.4 0.1 111.0 0.2 2013.458 2878 9.15 9.97 6 2 16406+0413 STFA 31AB 229.7 0.7 69.8 1.3 2012.553 1038 5.76 6.92 1 1 16560+4643 KZA 122AB 261.6 0.1 79.9 0.1 2013.518 2321 10.14 11.44 3 1 16560+4643 KZA 122AC 239.1 0.1 141.9 0.2 2013.518 1891 10.14 11.93 3 1

Table 2 continues on next page.

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Double Star Measures Using the Video Drift Method - IV

Table 2 (continued). Results of 240 double stars using the video drift method.

# x-y WDS Discoverer PA° σ-PA Sep" σ-Sep Date Mag Pri Mag Sec Drifts Nights pairs 17004+3058 HLM 8 347.3 0.8 19.6 0.2 2013.510 2357 11.61 11.45 3 1 17050-0504 LDS 585AB 122.2 0.1 185.0 0.2 2013.521 1336 7.86 10.14 3 1 17068+3356 SLE 78AB 99.0 0.4 59.6 0.4 2011.507 735 7.96 11.27 1 1 17068+3356 SLE 78AC 114.0 0.8 58.2 0.6 2011.507 736 7.96 12.15 1 1 17068+3356 SLE 78BC 202.0 2.8 15.5 0.7 2011.507 858 11.27 12.15 1 1 17068+3356 SLE 78AB 98.7 0.2 59.6 0.2 2013.510 2033 7.96 11.27 3 1 17087+3407 KU 115 58.3 0.4 35.7 0.2 2013.510 2261 9.79 10.31 3 1 17418-2032 ARA1129 270.5 1.7 6.0 0.3 2013.523 1569 11.57 12.1 2 1 17507+0755 STF2230AB 86.7 0.2 46.7 0.2 2013.458 1815 9.21 9.85 3 1 17507+0755 STF2230AC 112.6 0.3 40.0 0.2 2013.458 1815 9.21 11.12 3 1 17520+1520 STT 338AC 200.9 0.8 32.8 0.3 2013.518 2006 7.21 13.6 3 1 17520+1520 STT 338AD 246.6 0.1 95.6 0.2 2013.518 1556 7.21 10.6 3 1 17534+1058 STTA160 190.9 0.1 101.0 0.2 2013.458 1971 8.36 9.64 3 1 17535-2231 ARA1828 94.8 2.0 6.7 0.3 2013.523 1612 11.31 12.3 2 1 18006+0256 H6 2AC 142.4 0.2 53.9 0.2 2012.848 2021 3.96 8.06 2 1 18032+0755 STTA164 359.7 0.1 50.3 0.2 2013.458 2071 8.26 9.28 3 1 18089+1802 BPM 729 91.7 0.6 23.3 0.3 2013.523 1489 10.71 11.84 2 1 18093+0909 RUC 24AC 35.4 0.7 22.2 0.3 2013.523 1462 9.0 13.0 2 1 18111+3258 ES 185 286.1 1.0 12.6 0.2 2013.510 2360 9.89 10.99 3 1 18117+4020 UC 3526 136.3 0.6 24.8 0.2 2013.523 1904 9.9 12.7 2 1 18118+3406 DAM 630 39.6 1.4 14.8 0.3 2013.523 1788 12.6 14.3 2 1 18143-1902 ARA 740 52.5 1.9 8.8 0.3 2013.521 1532 12.02 12.0 2 1 18597+1002 HJ 5506 60.5 1.4 12.9 0.3 2013.521 1465 10.95 11.9 2 1 19053-0610 BU 974AC 118.8 0.8 19.6 0.4 2013.521 1426 9.96 12.6 2 1 19079-2259 ARA2256 357.3 1.2 7.7 0.3 2013.521 1605 11.79 11.9 2 1 19260+3555 BU 1286AB 45.1 0.7 22.5 0.2 2013.521 1789 9.45 10.49 2 1 19278+3709 ALI 392 196.0 1.7 14.6 0.4 2013.521 1823 12.00 12.3 2 1 20060+3546 ES 25AF 329.0 0.1 95.5 0.1 2013.510 4267 7.89 6.78 6 2 20060+3546 SHJ 315AD 235.6 0.4 20.4 0.1 2013.510 4773 7.89 8.73 6 2 20060+3547 BU 429AC 31.8 1.2 11.8 0.2 2013.510 2368 6.78 11.0 3 1 20060+3547 BU 429AE 108.7 0.3 28.7 0.2 2013.510 4535 6.78 11.42 6 2 20060+3547 SHJ 314AD 297.4 1.2 10.8 0.2 2013.121 2459 6.78 9.49 3 1 20060+3547 SHJ 314AF 28.5 0.2 35.5 0.1 2013.510 4774 6.78 7.30 6 2 20140-0403 HJ 909 128.4 0.6 15.3 0.2 2012.712 4107 11.00 12.07 6 2 20152-0330 STF2654 232.7 0.5 14.4 0.1 2012.712 4159 6.96 8.14 6 2 20262+3547 SEI1125AB 248.4 0.7 19.3 0.2 2013.121 2250 8.7 11.5 3 1 20270+3329 HJ 1515 24.7 0.8 15.7 0.2 2013.121 2397 9.31 11.28 3 1 20302+1925 S 752AC 287.8 0.4 106.5 0.5 2012.685 3618 6.80 7.30 2 1 20431+1705 BLL 51 159.4 0.1 55.7 0.1 2012.745 4192 8.72 9.56 6 2 20469+3252 ARG 93 87.8 1.0 10.9 0.1 2012.688 2495 8.30 9.59 3 1 20493+3314 ES 31AB 236.8 0.9 13.7 0.2 2012.688 2508 9.62 10.92 3 1 20493+3314 ES 31AC 142.6 0.8 19.2 0.2 2012.712 2413 9.62 9.50 3 1 20598+1649 STTA213 36.6 0.1 70.5 0.1 2012.745 3794 6.66 9.22 6 2 21126+0149 BAL1583 5.7 1.0 8.2 0.2 2012.688 4221 10.17 10.45 6 2 Table 2 concludes on next page.

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Double Star Measures Using the Video Drift Method - IV

Table 2 (conclusion). Results of 240 double stars using the video drift method. # x-y WDS Discoverer PA° σ-PA Sep" σ-Sep Date Mag Pri Mag Sec Drifts Nights pairs 21218+0202 STF2787AB 20.2 0.3 22.4 0.1 2012.688 4099 7.49 8.64 6 2 21218+0202 STF2787AC 94.1 0.1 70.7 0.2 2012.751 3366 7.49 11.41 6 2 21376+0643 STT 443AB 348.5 0.9 8.0 0.1 2012.751 4245 9.47 9.67 6 2 21377+0637 STFA 56AB 348.6 0.2 38.6 0.1 2012.751 4208 6.18 7.50 6 2 21420+1856 STF2818AB 24.6 0.3 26.3 0.1 2012.745 4295 7.38 10.24 6 2 21434+3817 S 799AB 60.2 0.3 149.7 0.6 2012.685 2066 5.69 7.00 1 1 21441+0709 STTA222 257.5 0.1 87.6 0.1 2012.712 3229 7.49 8.47 6 2 21543+1943 STF2841A,BC 109.6 0.3 22.4 0.1 2012.745 4165 6.45 7.99 6 2 21560+1948 ALL 4 208.7 0.4 19.0 0.1 2012.745 4347 9.31 9.77 6 2 22207+2457 STF2895AB 47.9 0.6 13.7 0.1 2012.753 4499 8.49 9.95 6 2 22269+4943 BU 380AB 323.6 1.0 24.1 0.3 2012.688 2980 8.15 11.29 3 1 22269+4943 STTA234AC 133.7 0.2 36.1 0.1 2012.688 6078 8.15 8.49 6 2 22301+4921 FRK 11 90.5 0.1 67.4 0.1 2012.688 5178 6.55 10.74 6 2 22586+1203 STTA241 160.6 0.1 84.0 0.1 2012.751 3971 8.28 8.37 6 2 23075+3250 STF2978 145.4 5.6 8.0 0.8 2010.767 2436 6.35 7.46 1 1 23100+1426 STF2986 269.3 0.2 31.1 0.1 2012.751 3970 6.61 8.88 6 2 23134+1104 STF2991 358.7 0.3 32.5 0.2 2012.745 2810 5.96 10.16 5 2 23283+0604 H 5 48 1.5 0.1 90.1 0.2 2012.712 2052 7.43 9.54 3 1 23283+2556 BUP 237AB 282.6 0.3 54.6 0.3 2013.882 1429 8.80 13.0 2 1 23283+2556 BUP 237AC 261.4 0.3 66.6 0.4 2013.882 1364 8.80 13.1 2 1 23307+0515 STF3019 184.4 0.9 10.7 0.2 2012.712 2115 7.77 8.37 3 1 23412+0616 STF3031 309.9 0.5 14.0 0.1 2012.712 4107 7.80 8.58 6 2 23549+2929 STTA252 144.3 0.2 110.8 0.4 2012.847 6030 6.77 8.37 3 1 Table 2 Notes 17h 41m 43.18sec, -20° 32' 21.4″, which is 1.8' dif- ferent from the WDS catalog values. All magnitudes were taken from the WDS catalog. All position angle/separation measurements are of the This updated coordinate information was submitted Equator and Equinox of date. to the USNO prior to publication.

Column titled “# x-y pairs” is the total combined no. of (x,y) pairs (video frames) from all drift runs. All video frames were used, none were discarded.

The column “drifts” is the number of separate drifts made. “Nights” is the number of successive nights drift runs were made for that system.

WDS 04368-1736 ARA 154 – Corrected RA, DEC coordinates are (J2000) 4h 36m 44.3s, -17° 35' 20.3"

WDS 05404-2151 ARA 1278 – Corrected RA, DEC coordinates are (J2000) 5h 40m 22.6s, -21° 51' 05.7"

WDS 17418-2032 ARA 1129 – Corrected RA, DEC coordinates are (J2000)

Vol. 10 No. 3 July 1, 2014 Journal of Double Star Observations Page 222

Double Star Measures Using the Video Drift Method - IV

(Continued from page 215) Consistency of the Method The video drift method maintains consistent results over multiple drifts and over several nights. The video drift method is ideally suited for high school and col- lege students that are proficient with computers. Acknowledgements This research makes use of the Washington Double Star Catalog maintained at the US Naval Observatory. We also thank Dave Herald and Chris Peterson for helpful comments on video error sources and calibra- tion procedures. References Miyashita, K. 2006, LiMovie, Light Measurement Tool for Occultation Observation Using Video Record- er, http://www005.upp.so-net.ne.jp/k_miyash/ occ02/limovie_en.html Nugent, R. and Iverson, E. 2011, Journal of Double Star Observations, 7, No. 3, 185-194 (Paper I) Nugent, R. and Iverson, E. 2012, Journal of Double Star Observations, 8, No. 3, 213-222 (Paper II) Nugent, R. and Iverson, E. 2013, Journal of Double Star Observations, 9, No. 2, 113-121 (Paper III) Rudiak-Gould, Ben, 2008 http://neuron2.net/ www.math.berkeley.edu/benrg/avisynth.html

Vol. 10 No. 3 July 1, 2014 Journal of Double Star Observations Page 223

DSLR Double Star Astrometry Using an Alt-Az Telescope

Thomas G. Frey1, David Haworth

1. California Polytechnic State University, San Luis Obispo, California

Abstract: The goal of this project was to determine if the double star’s angular separation and position angle measurements could be successfully measured with a motor driven, alt-azimuth Dobsonian-mounted Newtonian telescope (without a field rotator), and a digital single-lens re- flex (DSLR) camera. Additionally, the project was constrained by using as much existing equip- ment as much as possible, including an Apple MacBook Pro laptop and a Canon T2i camera. This project was additionally challenging because the first author had no experience with astro- photography.

effects can be minimized, and an accurate reading ob- Introduction tained. Exposure times have to be carefully selected to Double star (DS) observations throughout the last avoid being under or over exposed. Under exposure of 200 years have used a variety of devices to measure the double stars is often accompanied by too few reference position angle and angular separation such as the Lyot- stars. Over exposure of the star image is clipped at the Carmichael micrometer, Bi-Filar micrometer, and astro- maximum thus reducing the subpixel resolution that is metric reticle eyepieces. Separation measurements us- possible with correct exposure. ing reticle eyepieces are limited by seeing conditions and wide angular separations. Rapid scintillation can Instrumentation and Software lead to erroneous readings on the linear scale of the as- The telescope used in this study was an 18 inch trometric eyepiece. The digital age has introduced pho- f/4.5 Newtonian manufactured by Obsession (Figure 1), tographic methods involving charged couple devices equipped with a ServoCAT GOTO drive. The DSLR (CCD) and complementary metal-oxide-semiconductor was a Canon T2i with an 18-megapixel CMOS sensor (CMOS) image sensors. Astronomers have usually rec- providing 14-bit RAW image files and 8-bit JPEG files. ommended equatorially-mounted telescopes, rather than It features an enhanced LiveView mode that simplifies alt-azimuth (alt-az) mounts, due to the problem of field focusing on the stars. Accurate focus was accomplished rotation encountered with the latter type. Field rotation by using a Bahtinov mask [2]. Frey used a MacBook can alter the actual measured position angle as the DS Pro equipped with OS 10.8.4 and a partitioned hard is allowed to drift across the field of view. High field drive with Microsoft Windows 7. Software used in this rotation is observed in the north (0°), south (180°), and project included ImageJ [3], IrfanView [4], and Herbert toward the zenith. Low field rotation is observed in the Raab’s Astrometrica [5] to obtain right ascension (RA) east (90°) and the west (270°). The magnitude of the and declination (Dec) values of each star. The data was field rotation is dependent upon the cosine function of processed by Frey using an Excel spreadsheet [6] and the azimuth direction [1]. yielded the position angle and separation. Frey also To circumvent these problems and still use the alt- used PlateSolve3, software being developed by Dave az mounted telescope, DSLR photographs can be taken Rowe of the Pinto Valley Observatory, that reduces of a DS and the digital information can be reduced with double star FITS, BMP, PNG, GIF, and JPG files and a variety of commercially available software to obtain converts them directly to position angle and angular the position angle and angular separation. With short separation values. exposure times, both the field rotation and scintillation Haworth used AIP4WIN V2.4.8B [11] software to

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Figure 1. Obsession telescope with a Bahtinov mask and Canon T2i Figure 2. This is KUI 82AB,C , discussed in the DSLR camera. text.

determine the angular separation and position angles. The images used were RAW CR2 files from images tak- ally, PCs have been used, rather than Apple Macintosh en by Frey. Haworth used AIP4WIN because it reads computers because astrometry software is usually PC RAW Canon DSLR images, it plate solves the positions based. The authors’ hope is, by outlining these steps, of the double stars, and will give repeatable star centroid that amateur astronomers with alt-az telescopes and determination for both round and non-round star images. DSLR cameras are able to do serious double star re- Haworth’s computer is a MacBook Pro running OS X search. The following summarizes the camera, tele- 10.8.5, Mountain Lion, running a Parallels desktop for a scope, and computer operations carried out. Mac Virtual machine to run Windows 7 Professional Camera Settings for the Canon T2i SP1, Windows XP Professional SP3 and Ubuntu 12.04.1 Disengage the auto flash and autorotation. Set the LTS. picture style for zero saturation. Set the mirror lockup. If Each Canon CR2 image file was ~30MB (too large your camera has a reduced noise effect setting, engage to send by email) so the authors exchanged images by it. Set the camera to take both RAW (CR2) and JPG im- using Xoom Data Services, Inc. LargeFilesASAP, a free ages simultaneously. Set the timer for 2-second delay large file transfer service. and/or use a shutter cable. Set the shooting mode to Tv. Locale and Observing Conditions Begin with 1.0-second exposures at ISO 800. Verify that The photographs were taken at Santa Margarita the camera date and clock settings are accurate within Lake in San Luis Obispo County near Santa Margarita, one second. Replace the lens with a 2-inch T-ring. CA at 35.34 degrees North latitude and 120.50 degrees Telescope Setup West longitude. Observations were conducted over the Insert the camera into the focusing tube and align period March 21- May 30, 2013. Observing conditions the bottom of the camera with the optical path from the varied over this period. Most observing sessions in- primary mirror. Align the telescope with reference stars volved low humidity and good seeing with only moder- using the Live View of the camera. Be sure the reference ate scintillation. The marine layer from the Pacific stars are centered on the camera’s LCD screen. Place a Ocean was never a problem. Bahtinov mask on the front of the telescope and center a bright star’s image, again using the Live View. A hand- Procedure: Astrophotography and Data Reduc- held magnifier will assist you in positioning the Bahti- tion nov image on the screen. Rotate the focusing knob until A fairly detailed account will be given for the dou- the central diffraction spike is centered on the star. Fo- ble star photography and software analysis because most cus until the central spike is located symmetrically be- astrophotographic methods incorporate equatorially tween the other two diffraction spikes. See Figure 3 [2]. mounted telescopes using CCD devices. Also, tradition- Remove the Bahtinov mask. Slew to the first double

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ber of star catalogs: PlateSolve3 uses UCAC4; where Astrometrica options are UCAC4, USNO-B1.0, PPMXL, and NOMAD. Move onto the next double star and repeat this se- quence. Photo Analysis Open iPhoto on the MacBook Pro and download all images from the camera. Get the exact time of each ex- posure by clicking on the “Info” button. Click on the RAW (or CR2) photo to be analyzed. DSLR RAW files are used by Astrometrica and AIP4WIN because the RAW CR2 files provide a greater dynamic range over JPG files which are limited to 256 levels. PlateSolve3 Figure 3. Bahtinov diffraction images. The central image shows the proper orientation of the central spike to attain maximum focus. can process JPG files, directly. Go to the file menu and (Wikipedia, http://en.wikipedia.org/wiki/Bahtinov_mask.) select “Reveal” in Finder, select “Original” file. Click and drag the file into a CR2 file folder on the desktop. Download all CR2 and JPG files onto a flash drive. star. Be sure it is centered on the LCD. This is important as field rotation is less at the center of the image and increases the farther away from the image center. Take Data Reduction an initial image of the double star. Use three different software programs to convert the Computer Setup for MacBook Pro Using OS X 10.8.4 DSLR photo files to position angle and angular separa- Activate Red Screen [7]. Download this initial im- tion values for the ten double stars. age. Open ImageJ and select the JPG image. Go to the Astrometrica Reduction analysis menu, select “Measure.” Using the square icon, Restart the MacIntosh using Bootcamp and open click and drag until the square box is centered around Microsoft Windows. Use Windows 7 for this procedure. the double star. Check to be sure the value is below 255. Use IrfanView to convert CR2 files to TIF files then use If it is 255, the maximum value possible, you must ei- ImageJ to convert the TIF files to FITS files. Open As- ther decrease the ISO, decrease the exposure, or adjust trometrica. Load the FITS file and determine the RA and both the ISO and exposure to avoid saturation of the im- Dec for the primary and secondary components. age. Take another test image. Once the value is below Excel Spreadsheet: Setup a spreadsheet to convert 255 (try for 240-250) select the line icon from the menu. the RA and Dec of the primary and secondary stars into Click and drag the line through the two stars. Go to the angular separation and position angle. The best guide- analysis menu and choose “Plot Profile.” Be sure two line is to follow Chapter 15 by Bob Buchheim in Argyle single peaks appear and that the tallest one does not [6]. have a flat top. PlateSolve3 Reduction If the peaks are distorted, refocusing with the Bahti- Restart the MacIntosh using Bootcamp. Use the nov mask may be necessary. Once the Maximum is be- Windows 7 O/S as with Astrometrica, either 32-bit or 64 low 255 and the focus is sharp, take a series of 10-15 -bit Windows 7 will function properly. Since Plate- images in rapid succession to be used for angular separa- Solve3 can use JPG files, it is unnecessary to convert to tion and position angle determination. The more images TIF or FITS files. Load the JPG files then plate solve the taken increases the quality of the data set statistics. image. Then by setting the primary star as reference and Logbook Entry the secondary star as the target, differential photometry Record, for each image taken: image number, date, converts the right ascension and declination of the two object name, right ascension and declination, constella- stars into position angle and separation. tion, approximate time, exposure time, ISO, and ImageJ AIP4WIN Reduction Max value. Later on you can get the exact time from the The following describes Haworth’s four-step pro- camera log. Important: be sure the target double star has cess. enough reference stars in the fov for proper analysis First, Cartes du Ciel [13] is used to verify the double by Astrometrica, AIP4WIN, and PlateSolve3. Eight stars and its orientation to north. Its orientation to north to twelve reference stars will be sufficient for most im- is used in the AIP4WIN astrometric tool to rotate the ages to obtain a reduction. Various programs use a num- reference stars.

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Second, AIP4WIN is used to convert the Canon col- ence stars. or CR2 file to a monochrome FIT file. AIP4WIN has Fourth, AIP4WIN measure distance is used to meas- two settings windows that need to be configured to read ure the separation distance (rho) and position an- Canon CR2 files. The first window is the Bayer Ar- gle (theta). ray Color window that configures Bayer type red, green, For double stars KUI 82AB,C a Python script was green and blue for the Canon CR2 files. The second created by Haworth to calculate and plot the separa- window is the DSLR and Bayer conversion Settings tion distance (rho) and position angle (theta) of double window that uses the Bi-Linear Interpolation for the De- stars given the double stars RA and Dec in a CSV txt Bayerization algorithm (private communication with file. Also, the Python script will take multiple measure- Richard Berry). Set the DeBayer to Convert Color to ments and perform statistics on the data set and plot the Gray Scale. Set all RGB scales to 1.0. The image pixel result. The Python script was developed with the free size is set to 4.3 microns and the monochrome image is Python Canopy Express programming environment. Ha- saved as a FIT file. worth uses Canopy Express on computers with the Mac Third, using the Image Display Control, the Us- OS X and Windows 7 operating systems. Cano- er Black/White Values are adjusted to show the image py Express simplifies using Python because it installs without the background noise. Usually only the White and manages the updates to over 30 preconfigured Py- Point needs to be increased. The Control Zoom is adjust- thon packages. ed to 25% or 20 % to see the complete image. The AIP4WIN astrometric tool is used to plate solve the im- Data for Ten Double Stars age. Up to 24 reference stars are used in the plate solve Table 1 shows the literature data and observed of the image. The target stars are the double stars and measurements of position angle and angular separation they are not used as reference stars. The AIP4WIN as- for the 10 double stars studied. The angular separations trometric tool allows you to manually start the plate ranged from approximately 18-90 arc seconds. The dif- solving process with the bright stars first. As more refer- ference in magnitudes between the primary and second- ence stars are chosen the plate solve measurements are ary stars ranged from 0.2-1.4 to ensure similar signal refined and updated. At the end of the plate solv- strength during software reduction. Frey’s and Ha- ing process you can save the details to a file. The USNO worth’s data were obtained using the outline presented -A2.0 catalog with 526,280,881 stars with complete cov- in the procedure above. Most values in Table 1 are based erage of the sky was used for the plate solve refer- on single image reduction for each double star. For

Table 1: Position angle and angular separation for ten double stars. Literature values (WDS) and DSLR results are shown. *Values are averages of 3 reductions of same DSLR image. **WDS listed 3 different PAs for 2012: 311.9, 309.0, 314.1. Middle value was chosen for reference. ***Insufficient reference stars on image to obtain a solution. #Values are average of 5 reductions of different DSLR images. Astrometric PlateSolve3 Lit. Values (WDS) AIP4WIN Results Bessel. Results Results Object Epoch PA Sep PA Sep PA Sep PA Sep Epoch (degs) (asec) (degs) (asec) (degs) (asec) (degs) (asec) STF 627 AB 2013.22 259.9 20.94 2012 256.84 21.52 260.1 21.3 260.27 21.30

STF 697 AB 2013.22 286.0 25.82 2013 284.06 26.75 285.97 26.08 284.54 25.88

STF 817 2013.28 73.1 18.65 2010 75.08 17.87 73.49 18.32 73.44 18.25

STF1347 2013.33 311.9** 21.18 2012 310.67* 20.92* 310.25 21.24 312.42 21.21

STF1369 AB 2013.33 149.4 24.96 2010 149.16 23.99 *** *** 149.46 24.93

STF1399 2013.33 175.3 30.61 2009 175.46 30.30 175.47 30.7 175.57 30.53

S 686 2013.37 3.9 50.00 2012 4.84 50.08 4.20 49.99 4.23 50.08

STF2166 AB 2013.41 282.2 27.16 2012 282.74* 27.95* 281.66 27.25 281.83 27.33

KUI 82 AB,C 2013.41 312.8 49.87 2010 313.46# 50.13# 313.77# 50.09# 313.66# 50.15#

STF2185 AC 2013.41 250.1 90.01 2006 252.43 90.44 252.13 91.99 252.12 91.93

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Frey’s Astrometrica observations, two are averages of ations (SD) and standard errors of the mean (SEM) were three reductions of the same DSLR image; one is the calculated to determine the variance for the five differ- average of five different DSLR images. Frey wanted to ent images. AIP4WIN and PS3 statistics show a tighter compare the statistics of Astrometrica’s reduction of the grouping. The position angles determined by Astromet- same image several times versus a series of different rica’s reduction of images 5971 and 5972 were signifi- images of the same target. All position angles are given cantly lower than the other three that caused the broader in degrees, all angular separations in arc seconds. The spread. See Table 2. literature values are based on the most recent entry in Figures 4A&B plot the right ascension in degrees on the Washington Double Star Catalog (WDS) [8] for that the X-axis and the declination in degrees on the Y-axis target. for five different DSLR images of KUI 82AB,C, re- duced by Astrometrica. Note the exponential number on Statistical Analysis: the far right of the X-axis. This value is to be added to If astrometric reticle eyepieces are use to determine the value indicated on the X-axis to get the actual value the position angle and angular separation of a double in degrees. A similar value is at the top of the Y-axis for star, the observer must take many measurements to de- declination. In the top image we see how the primary crease the chance of bias and random error. The obser- stars are grouped within a 6 arc second diameter circle. vations are fleeting and cannot be recovered. With We also see a slight spread and change of position angle DSLR or CCD techniques, a permanent record is ob- as the secondary stars are illustrated on the bottom. tained that can be accessed anytime for reexamination. Compare the data illustrated in Figures 4A&B with Yet, “putting all your eggs in one basket”, in this case, that in Figures 5A&B where the same five images were taking a single photo and basing your results on that, is reduced by AIP4WIN instead of Astrometrica. Note that inappropriate from a scientific approach. This initial both the primary and secondary stars are grouped within study was undertaken with the goal of attempting DSLR a circle about 1 arc second in diameter. The AIP4WIN double star evaluation so most double star targets have software [11] is better in converting the DSLR CR2 files only a few recorded photos. Therefore statistical analy- into a tighter right ascension and declination display. sis was not carried out for the bulk of the observations. Figures 4 and 5 were created by Haworth using the However, one target, KUI 82AB,C, an optical dou- Python script [12] given the right ascension and declina- ble star in Hercules, was photographed five times in rap- tion. id succession. All FITS files were analyzed by Astro- It was also noticed that every time an Astrometrica metrica (Frey) and by AIP4WIN (Haworth). JPG files analysis was carried out only slight differences in the were analyzed by PlateSolve3 (PS3). The standard devi- (Continued on page 229)

Table 2: Standard deviation and standard error of the mean for 5 different image reductions of KUI 82AB,C

AIP4WIN Data Astrometrica Data PlateSolve3 Data Exposur PA Separ PA Separ PA Separ Image (sec) (degs) (asec) (degs) (asec) (degs) (asec) 5970 2.0 313.741 49.83 313.75 49.75 313.64 50.09 5971 2.5 313.758 50.24 312.96 50.18 313.69 50.22 5972 2.5 313.652 50.45 313.00 49.86 313.55 50.44 5973 2.5 313.941 49.86 313.82 49.82 313.78 50.07 5974 3.2 313.756 50.06 313.77 51.03 313.65 49.94

Aver 313.770 50.09 313.46 50.13 313.66 50.15

SD 0.094 0.23 0.39 0.48 0.083 0.19

SEM 0.042 0.10 0.18 0.21 0.037 0.085

WDS 313 49.8 313 49.8 313 49.8

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Figures 4A&B. Right ascension and declination of the primary Figure 5A&B. Right ascension and declination of the primary and and secondary stars for KUI 82AB,C are plotted for 5 different secondary stars for KUI 82AB,C are plotted for 5 different DSLR DSLR images, 5970-5974, showing the grouping pattern. Files images, 5970-5974, showing the grouping pattern. Files reduced reduced by Astrometrica. by AIP4WIN.

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(Continued from page 227) against the Besselian dates of those observations. The RA and Dec were observed if the same image was re- slope of the change in position angle was generated by analyzed. This difference was due to the hands-on ma- using the Exponential Trendline feature in Microsoft nipulation of Focal Length and Rotation indictated by Excel. Two of these plots are shown in Figures 6A&B. the software to obtain the RA and Dec. It would be in- A majority of the changes in position angle over the teresting to compare the SD and SEM for the position recorded periods differed by a small amount for the ten angle and separation values for KUI 82AB,C obtained double stars. For the first eight double stars listed the from five different images and those obtained from anal- range varied from 0.9 to 3.5 degrees. The latter two dou- ysis of five reductions of the same image. See Table 3. ble stars showed more significant changes during the Table 3 lists the same image, 5971, reduced five recorded period. Figures 6A&B show representative times with Astrometrica. This shows that the variance in samples of both types of change. Figures 6A&B plot the the reduction of the same image multiple times is ex- Besselian year vs. position angle (degrees) on the left tremely small. Note that the SD for the Astrometrica vertical axis and separation (arc seconds) on the right separation and position angles in Table 3 for the same vertical axis. Note the fairly linear change in position image (PA, 0.05920; Sep, 0.06199) are much smaller angle for the two plots. Series 1 refers to the position than the SD Astrometrica data obtained for reducing five angle changes; series 2 to the separation changes. different images (PA, 0.39297; sep, 0.47657) in Table 2. There is a measurable change in the position angle The SD for the five different images reduced by for KUI 82AB,C over the 100+ years of observations. A AIP4WIN (PA, 0.09437; Sep, 0.23460) more closely higher order equation should be used to determine the resembles the SD for the same five images reduced by position angle for this system. However, by using the Astrometrica, indicating a smaller variance in data pro- slope generated in the graph of Figure 6, a position angle cessing using AIP4WIN. can be projected from the most recent WDS reported values to the date of the observation made in this study. Comparison of Past and Present Observations: This can then be compared to the observed values in this Brian Mason [8] provided all of the past position study. For KUI 82AB,C, the most recent WDS position angle and separation data from the WDS for the ten dou- angle from 2010.6 was 312.8 degrees. If the PA slope ble stars studied. The overall change in position angle determined from the Besselian date vs. PA graph is ap- (PA) from initial studies to the present is shown in Table plied to the most recent WDS position angle value and 4. The position angle from past observations is plotted (Continued on page 231)

Table 3: Standard deviation and standard error of the mean for 5 Astrometrica reductions of the same KUI 82AB,C image 5971. Itera- RA Dec RA Dec PA Separation tion primary primary secondary secondary degs asec 1 17 29 19.95 29 23 27.6 17 29 17.14 29 24 1.6 312.794 50.047

2 17 29 19.94 29 23 27.4 17 29 17.14 29.24 1.4 312.896 49.951

3 17 29 19.88 29 23 28.3 17 29 17.08 29 24 2.3 312.896 49.951

4 17 29 19.95 29 23 28.1 17 29 17.14 29 24 2.2 312.878 50.115

5 17 29 19.90 29 23 28.1 17 29 17.10 29 24 2.2 312.980 50.019

Average 312.889 50.017

SD 0.059 0.062

SEM 0.026 0.028

WDS 313 49.8

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Table 4: Change in position angle for the ten double stars observed from past to current study obser- vations. * One outlier not counted in slope determination. Change PA; max to Slope: Bess. Date vs Double Star Period (years) min (degrees) PA (degs/year) STF 627AB 1799-2012 2.6 -0.0055*

STF 697AB 1828-2013 2.4 +0.0075

STF 817 1830-2011 2.8 +0.0064

STF1347 1825-2012 3.0 +0.0071

STF1369AB 1831-2012 3.5 +0.0125

STF1399 1827-2009 1.4 +0.0032

S 686 1825-2012 0.9 -0.0020

STF2166AB 1831-2012 1.4 -0.0056*

KUI 82AB,C 1902-2010 43.2 +0.3479

STF2185AC 1864-2006 59.7 +0.4348

Figures 6A&B: (a) STF 2166, PA slope -0.0056, (b) KUI 82AB,C, PA slope +0.3479.

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(Continued from page 229) to Herbert Raab in Austria for his Astrometrica. The projected to the Besselian day the photograph was taken authors would like to thanks Dave Rowe of Pinto Valley (2013.4, ~2.8 years), we get: Observatory for allowing us to test his newly developed PlateSolve3 software to reduce our data. And Tom Frey Change in PA of KUI 82AB,C = (2.8 yrs)(+0.3479 would like to express his gratitude to his co-author, degs/yr) = +0.97 degrees Dave Haworth, for the many hours spent training him in the basics of astrophotography and software manipula- Add this to the most recent WDS PA value, we get: tion.

Projected WDS PA in 2013.4 = 312.8 + 0.97 = References 313.77 degrees 1. Frey, Thomas G., Journal of Double Star Observa- Astrometrica’s value: 313.46 degrees tions, 6(4), 216-226, 2011. AIP4WIN’s value: 313.77 degrees PlateSolve’s value: 313.66 degrees 2. Bahtinov Mask, www.deepskywatch.com/Articles/ make-bahtinov-mask.html. The change in position angle for the initial 8 double 3. ImageJ, rsb.info.nih.gov/ij/. stars between the last reported WDS value and the ob- servations are too small to make this comparison. 4. IrfanView, www.irfanview.com. Conclusions 5. Astrometrica, shareware, www.astrometrica.at. This study has shown that using an alt-az motor- 6. Buchheim, Bob, Chapter 15, Observing and Measur- nd tracking telescope, a MacBook Pro computer with a par- ing Visual Double Stars, 2 Ed., Springer, 2012, R.W. titioned hard drive using a Windows 7 operating system, Argyle, Editor. and a Canon DSLR camera using short exposure times, 7. Red Screen, Version 2.0.1 (1), Chris Wood, http:// accurate double star measurements of position angles interealtime.com/redscreen-advanced-screen-dimming- and angular separation can be accomplished. Although for-mac-os-x/. multiple images of each double star were not taken in a majority of cases, fairly accurate measurements, that 8. Mason, B., The Washington Double Star Catalog, closely agree with literature values, can be obtained. 2009, Astronomy Department, U.S. Naval Observatory. Suggested future studies should concentrate on taking 9. The SkyX software, http://www.bisque.com/sc. multiple images and stacking them, using this feature in the Astrometrica, AIP4WIN, and PlateSolve3 software. 10. Aladin Sky Atlas, aladin.u-strasbg.fr. This will result in less noise in the photos, possibly lead- 11. The Handbook for Astronomical Image Processing ing to more accurate reductions. When selecting the with AIP for Windows (AIP4WIN) software, http:// double stars for study, the authors recommend examin- www.willbell.com/aip/index.htm. ing visual sources like The SkyX [9] or Aladin [10] im- ages to be sure sufficient reference stars are close by for 12. Python Canopy Express, Enthought Scientific Com- successful reductions. Future studies might also consider puting Solutions, https://www.enthought.com/products/ using a Barlow lens in conjunction with the DSLR cam- canopy/compare-subscriptions/ era so binaries with smaller angular separations can be examined. The limiting factor here would be finding 13. Cartes du Ciel, http://www.ap-i.net/skychart/ reference stars within the field of view during reduction. Acknowledgements The authors would like to express thanks to Jo- seph Carro and Brittany McCrigler for reviewing this paper and for their suggestions. Special thanks goes to Bob Buchheim and Tom Smith for assistance in setting up the spreadsheet for RA and Dec conversion to posi- tion angle and separation. Also a hearty recognition goes

Vol. 10 No. 3 July 1, 2014 Journal of Double Star Observations Page 232

Double Star Measurements at the Southern Sky with 50 cm Reflectors and Fast CCD Cameras in 2012

Rainer Anton

Altenholz/Kiel, Germany e-mail: rainer.anton”at”ki.comcity.de

Abstract: A Cassegrain and a Ritchey-Chrétien reflector, both with 50 cm aperture, were used in Namibia for recordings of double stars with fast CCD cameras and a notebook computer. From superposition of “lucky images”, measurements of 39 double and multiple systems were obtained and compared with literature data. Occasional deviations are discussed. Images of some remarkable systems are also presented.

the other of type “Chameleon” (Point Grey). The main Introduction difference is the number and size of the pixels, 1024 x As in earlier work, the technique of “lucky imag- 768 of 4.65 µm square for the DMK31, and 1296 x 964 ing” was applied to effectively reduce seeing effects of 3.75 µm for the Chameleon. While the smaller pixel during recording of double star images by using short size of the latter helps in resolving close doubles, it pro- exposure times. With only the best frames being regis- duces somewhat more noise which, however, does vir- tered and stacked, the resolution can approach the theo- tually no harm in short exposures. Resolution values in retical limit of the telescope, and the accuracy of posi- terms of arcsec per pixel for the combinations of tele- tion measurements can even be better than this by about scopes and cameras are listed in Table 1 below. These one order of magnitude. In this paper, measurements on scaling factors were obtained with calibration stars (see double and multiple systems made in fall 2012 are re- Table 2 below), and agree with calculated values and/or ported. Star brightness range is mostly above 8 mag, earlier results within the error limits. and only in a few cases, some dimmer companions are Position angles are measured as usual by recording also imaged. While some systems are sufficiently well trails in east-west direction, while the telescope drive documented in the literature, and can be used for cali- was temporarily switched off. bration of the image scale, in the majority of cases, data Generally, I used a red or near infrared filter to re- are scarce or exhibit large scatter. About 31 pairs are duce seeing effects and the atmospheric spectrum, and binaries with more or less well known orbits. In some cases, deviations from ephemeris data are found and Table 1: Resolution values in arcsec/pixel for combi- possible causes are discussed. nations of telescopes and cameras, with and without a nominal 2x Barlow lens. Ratios agree with earlier Instrumental measurements within the error limits of about ± 0.5%. Most recordings were made with a 50 cm telescope Likewise, the ratio for the two cameras corresponds to of Ritchey-Chrétien type (Alluna, Germany), which has the ratio of the pixel sizes. recently been installed at the Internationale Amateur- Sternwarte (IAS) in Namibia [1]. The focal length is 4.1 camera DMK31 Chameleon m. Some additional observations were done with a 50 telescope w/o B w B w/o B cm Cassegrain with focal length 4.5 m, which I have already used in earlier years [2]. For most recordings, 50 cm Cassegrain 0.212 not used 0.171 the magnification was about doubled with a Barlow 50 cm RC 0.234 0.121 not used lens. Imaging was done with two b/w-CCD cameras, one of type DMK31AF03 (The Imaging Source), and

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especially when using the Barlow lens, to reduce chro- matic aberration. A few systems with color contrast were in addition recorded with green and blue filters in order to produce RGB composite images. Exposure times varied between 0.5 msec and 100 msec, depending on the star brightness. Under good seeing conditions, some systems were also recorded with exposures up to 2 sec, in order to image faint companions. In cases of large differences of brightness of the components, the main star became over- exposed, and its position could eventually be determined by the diffraction spikes from the secondary mirror cell. More details of the technique and image processing are for example described in ref. [3]. Results All measurements are listed in Table 2, which is fol- lowed by individual notes. Numbering of the notes (last column at right) is with rounded R.A. values, which may Fig. 1: Plot of the residuals of rho versus rho (50cm RC with make locating in the listings easier. Names, position and DMK31 camera). Semi-logarithmic scale. Open symbols refer to magnitude data are taken from the WDS [4]. Several sys- recordings with Barlow, full dots to no Barlow. Open squares are tems were recorded with different configurations of tele- data for the trapezium in Orion (see text). Some systems with large deviations are marked with their names, or for pairs in the trapezi- scope/camera. Measures of the position angle, P.A., and um with their designations. See also notes. of the separation, rho, were then averaged. N is the total number of recordings. Shaded lines denote systems which were used for calibration of the image scale (see below). The residuals, delta P.A. and delta rho, refer to the trends of literature data, if sufficiently available, or for binaries, to the currently assumed ephemeris. Main sources are the Fourth Catalog of Interferometric Measurements of Bina- ry Stars (“speckle catalog”) [5], and the Sixth Catalog of Orbits of Visual Binary Stars [6]. Data available up to early 2014 are taken into account, as of writing this arti- cle. In several cases, larger deviations were found, which often agree with trends of literature data, however. These will be discussed in more detail below. In other cases, literature data are so scarce and/or exhibit so large scatter that no reasonable residuals can be given. Discussion In Table 1, systems used for calibration of the image scale are marked with shaded lines, and comprise both measurements with and without Barlow. In Figures 1 and 2, for data obtained using the 50cm RC, individual resid- uals are plotted separately, partly in order to demonstrate that the calibration constants for both modes, as given above in the section Instrumental, are consistent. Data Fig. 2: Plot of the residuals of the P.A. versus rho (50cm RC with DMK31 camera). Semi-logarithmic scale. Open symbols refer to points on or close to the zero line are used for calibration recordings with Barlow, full triangles to no Barlow. Open squares by averaging. Some systems exhibit significant deviations are data for the trapezium in Orion (see text). Some systems with which are discussed in the notes or below. large deviations are marked with their names. Binaries gamma Generally, and according to earlier work, error mar- Lupi and rho Capricorni exhibit highly inclined orbits. See also gins for separation measurements are expected to be of notes. the order of ±0.02 arcsec, and not to exceed ±0.05 arcsec,

(Continued on page 237)

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Table 2: List of all measurements. Systems used for calibration of the image scale are marked by shaded lines. Posi- tion angles (P.A.) are in degrees, separations (rho) in arcseconds. N is the number of different recordings. Residuals delta P.A. and/or delta rho are given, when extrapolations of literature data appear reasonable. Notes with asterisks refer to figures shown below. P.A. rho delta delta PAIR RA + DEC MAGS DATE N NOTES meas. meas. P.A. rho SLR 1 AB 01 06.1 -46 43 4.10 4.19 98.1 0.48 2012.71 3 +1.6 -0.01 01 06* HJ 3423 AB 5.00 7.74 316.3 4.74 2012.70 1 -1.6 -0.22 01 15.8 -68 53 01 16 I 27 CD 7.84 8.44 324.3 1.05 2012.70 1 +2.5 -0.05 I 264 AB 01 31.6 -53 22 8.36 8.84 29.0 0.78 2012.72 1 -0.8 -0.09 01 32 DUN 5 01 39.8 -56 12 5.78 5.90 187.3 11.39 2012.71 1 -0.5 -0.30 01 40 JC 8 AB 6.42 7.36 156.7 0.57 1 -0.9 -0.04 03 12.4 -44 25 2012.72 03 12* HJ 3556 AC 6.42 8.76 188.6 3.75 1 * * BU 1004 04 02.1 -34 29 7.26 7.94 57.4 1.16 2012.720 2 +0.2 -0.04 04 02 HJ 3683 04 40.3 -58 57 7.33 7.45 89.2 3.71 2012.721 1 -0.5 +0.03 04 40 STT 98 05 07.9 +08 30 5.76 6.67 294.9 0.89 2012.721 1 ~0 -0.02 05 08* STT 517 05 13.5 +01 58 6.79 6.99 240.8 0.66 2012.721 1 -0.8 -0.01 05 14 STF 668 A,BC 05 14.5 -08 12 0.3 6.8 204.9 9.53 2012.721 1 * * 05 15 STF 748 AB 6.55 7.49 31.6 8.87 2 +0.6 -0.03 STF 748 AC 6.55 5.06 131.6 12.82 2 -0.4 +0.12 STF 748 AD 6.55 6.38 95.7 21.44 2 -0.3 +0.04 STF 748 AE 6.55 11.1 352.3 4.61 1 +1.3 +0.01 STF 748 BC 7.49 5.06 162.9 16.80 2 -1.1 ~0 STF 748 BD 7.49 6.38 120.2 19.29 2 -0.8 -0.01 STF 748 BE 7.49 11.1 240.5 6.05 1 +0.5 -0.15 STF 748 BF 7.49 11.5 153.4 20.49 2012.721 1 -0.6 +0.19 05 35.3 -05 23 05 35* STF 748 CD 5.06 6.38 61.6 13.36 2 -0.4 +0.06 STF 748 CE 5.06 11.1 322.0 16.56 1 +1.0 -0.04 STF 748 CF 5.06 11.5 119.7 4.70 1 -0.3 +0.10 STF 748 CG 5.06 16.7 33.8 7.67 1 +0.8 -0.03 STF 748 CH 5.06 15.8 269.3 9.44 1 -2.7 +0.04 STF 748 CZ 5.06 12.7 338.4 6.53 1 +1.4 -0.37 STF 748 DE 6.38 11.1 287.0 22.95 1 ~0 -0.15 STF 748 DF 6.38 11.5 221.2 11.46 1 -4.8 -0.54 DUN 23 06 04.8 -48 28 7.30 7.69 127.4 2.60 2012.70 1 +2.6 +0.12 06 05 R 65 AB 5.97 6.15 257.8 0.53 2012.70 1 ~0 +0.01 06 30 HDO 195 CD 06 29.8 -50 14 7.98 8.73 159.2 0.38 2012.70 1 -3.2 +0.01 06 30 DUN 30 AB,CD 5.97 7.98 311.7 11.77 2012.70 1 <0.3 ~0 06 30 AGC 1 AB 06 45.1 -16 43 -1.46 8.5 83.1 9.63 2012.72 1 -0.8 -0.09 06 45 DUN 252 AB 1.25 1.55 111.9 3.85 2012.70 2 -1.3 -0.01 12 27* DUN 252 AC 1.25 4.80 202.2 89.6 2012.70 3 ~0 * 12 27* ANT 1 AG 12 26.6 -63 06 1.25 10. 145.6 56.4 „ 1 -0.4 -0.3 12 27* ANT 1 AH 1.25 13. 166.7 47.3 „ 1 -0.3 -0.1 12 27* ANT 1 AI 1.25 12. 227.1 63.3 „ 1 +0.1 -0.6 12 27* RHD 1 AB 14 39.6 -60 50 0.14 1.24 262.7 5.05 2012.71 5 -0.6 +0.02 14 40

Table 2 concludes on next page.

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Table 2 (conclusion): List of all measurements. Systems used for calibration of the image scale are marked by shaded lines. Position angles (P.A.) are in degrees, separations (rho) in arcseconds. N is the number of different recordings. Residuals delta P.A. and/or delta rho are given, when extrapolations of literature data appear reasonable. Notes with asterisks refer to figures shown below. P.A. rho delta delta PAIR RA + DEC MAGS DATE N NOTES meas. meas. P.A. rho HJ 4786 15 35.1 -41 10 2.95 4.45 274.6 0.81 2012.72 1 -2.2 -0.02 15 35 COO 193 8.97 8.99 224.0 1.87 2012.72 1 * * 16 07.7 -38 02 16 08 BU 120 AB 4.35 5.31 3.1 1.36 2012.72 1 +0.5 +0.02 H 5 6 AC 16 12.0 -19 28 4.35 6.60 336.2 41.37 2012.72 1 * * 16 12 MTL 2 CD 16 12.0 -19 28 6.60 7.23 55.5 2.32 2012.72 1 ~0 ~0 16 12

BSO 13 AB 17 19.1 -46 38 5.61 8.88 256.9 10.15 2012.73 1 ~0 +0.08 17 19

I 252 19 01.5 -34 30 8.70 8.80 50.2 0.85 2012.70 1 * * 19 01 HDO 150 AB 19 02.6 -29 53 3.27 3.48 271.2 0.45 2012.71 4 +1.1 +0.01 19 02* HU 261 19 04.3 -21 32 7.87 8.06 186.6 1.27 2012.71 2 +0.3 +0.02 19 04 HJ 5084 19 06.4 -37 04 4.53 6.42 359.5 1.37 2012.72 1 -0.5 ~0 19 06 GLE 3 19 17.2 -66 40 6.12 6.42 349.6 0.51 2012.70 1 +3.0 -0.01 19 17 I 253 8.77 7.25 143.8 0.37 1 +0.7 +0.07 BU 142 8.12 8.69 283.6 1.06 1 ~0 +0.05 I 120 AB 8.31 8.02 187.5 0.39 1 +4.8 -0.01 HU 5141 AB-C 7.36 10.4 340.4 11.84 1 * * HDO 294 8.08 9.11 30.8 1.19 1 -3.7 -0.12 R 321 6.58 8.09 127.0 1.54 1 +1.7 -0.01 SHJ 323 AB 4.97 6.88 191.1 1.55 1 +1.9 -0.12 HU 200 AB 19 19.0 -33 17 5.38 7.31 120.5 0.32 2012.72 2 -0.7 -0.01 19 19* HU 5319 7.65 7.66 315.1 2.05 1 +0.1 -0.05 SHJ 345 AB 6.29 6.39 51.6 1.23 1 +1.1 -0.04 STF 2909 4.34 4.49 167.4 2.22 2 +0.2 +0.02 I 304 8.50 8.72 0.9 4.08 1 * * I 22 AB 7.29 8.91 175.0 0.56 1 ~0 +0.04 JC 20 AB 4.45 6.60 114.9 1.53 2 -0.4 -0.01 SLR 14 8.28 8.59 65.7 0.94 2 -1.8 -0.02 Notes: Terms “cpm” (common proper motion) and “relfix” (relatively fixed) refer to Burnham [7].

01 06: beta Phoenicis, binary, P = 168 y. See fig. 3. 01 16: kappa Tucanae, binary, P = 857 y, few data, own measure significantly deviates from currently assumed orbit, but seems to be consistent with earlier measurements from 2008 and 2009. Pair CD is close to kappa Tu- canae, binary, P = 86 y. All cpm. 01 32: in , AB binary, P = 250 y, rho AB deviates from ephemeris, but follows trend of literature data, too few data for AC. 01 40: , binary, P = 484 y, although an easy pair, only few data in the literature. 03 12: in Eridanus, AB binary, P = 45 y, well documented with speckle data. See fig. 3. 04 02: in Eridanus, binary, P = 282 y, orbit calculation has recently been refined. 04 40: in Dorado, binary, P = 240 y, orbit highly inclined. 05 08: in Orion, binary, P = 199 y, many speckle data. See fig. 3.

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05 14: in Orion, binary, P = 312 y, many speckle data. 05 15: Rigel, beta Orionis, relfix, large difference in brightness, few data. 05 35: theta1 Orionis, “trapezium”, residuals given vs. last entries in the WDS (as of 2014-02), for pairs combining A, B, C and D from 2013, for AE and CF from 2009, for CE from 2008, for BE and BF from 2006, for DE from 2002, and for DF from 1987, see text. 06 05: in Puppis, binary, P = 464 y, measured position deviates from orbit, but follows the trend of speckle data. 06 30: in Puppis, also known as DUN 30 AB, CD: another “double-double” with two binaries: AB: P = 52.9 y, CD: P = 101 y, all cpm. The separation of the two pairs is decreasing. WDS data for DUN 30 seems to refer to AC. 06 45: Sirius, alpha Canis Majoris, famous binary, P = 50.9 y. Large difference in brightness of the components makes measurement difficult. 12 27: alpha Crucis, AB binary, but no orbit listed. While rho(AB) has been monotonously decreasing for more than 150 years, the last entry in the WDS of 3.6” from 2012 appears to be much lower than expected. No residu- als for C given, because of too few data. Residuals of G, H, and I refer to own measurements of 2007. 14 40: alpha Centauri, AB binary, P = 79.9 y, well documented. 15 35: gamma Lupi, binary, P = 190 y, highly inclined orbit. 16 08: in Lupus, few data. 16 12: nu Scorpii, “double-double”, but no orbits known. Some scatter of data for AC. 17 19: also known as L 7194, in Ara, binary, P = 693.3 y. 19 01: in Sagittarius, few data, PA inc, rho slow dec ?, extrapolation ambiguous. 19 02: zeta Sagittarii, fast binary, P = 21.1 y. See fig. 3. 19 04: also known as H N 126, in Sagittarius, binary, P = 356 y. 19 06: gamma Coronae Australis, binary, P = 122 y, PA rapid inc, rho slow inc. 19 17: in Pavo, binary, P = 157 y. 19 19: in Sagittarius, binary, P = 60 y, highly inclined orbit, showcase, but only few data. See fig. 3. 19 28: in Sagittarius, binary, P = 162 y. Rho significantly deviates from actual ephemeris, but seems to follow the trend of literature data. See fig. 6. 19 49: in Pavo, AB binary, P = 61.1 y; AB-C: PA dec, all cpm, C physical. Few data, large scatter. 20 01: in Sagittarius, binary, P = 475 y, “premature orbit”, own measures significantly deviate from currently as- sumed orbit, but follow the trend of recent speckle data. 20 27: in Sagittarius, binary, P = 178 y. 20 29: rho Capricorni, binary, P = 278 y, orbit highly inclined, large residuals vs. ephemeris, own measure better follows the trend of recent speckle data. 20 39: tau2 Capricorni, binary, P = 200 y, large scatter of literature data. See fig. 3. 22 12: in Grus, few data. 22 27: 53 Aquarii, binary, P = 3500 y?, despite the long period, PA is rapidly increasing with about 4 degrees/year, as the companion is near periastron, while rho is only slowly decreasing. 22 29: zeta Aquarii, binary (ternary), P = 760 y, position of B has been deviating from the ephemeris in recent years, due to the pull of a companion not seen in the visible, but is now again near the calculated orbit. 22 47: in Grus, few data with large scatter. 22 55: tau2 Gruis, probably binary, no orbit, large variations of rho data, brightness ratio differs. 23 07: theta Gruis, cpm, PA and rho inc. 23 51: in Phoenix, binary, P = 117 y.

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(Continued from page 233) ever, a number of pairs seem to stand out more than this, at least in the range of small separations. As can be seen in particular binaries with highly inclined orbits, and in Figure 1, several pairs are clearly off, and many of again, several members of the trapezium cluster. these are binaries. As the residuals are calculated with Possible origins of deviations of PA and rho are al- respect to the current ephemeris, deviations may indi- ready mentioned in the notes list. In particular, the fol- cate that this is not up to date. In fact, in many cases, lowing binaries deserve further attention in the (near and residuals against the trend of recent measurements are far) future (in order of increasing R.A., listed here with found much smaller. An example is shown in Figure 6 the note numbers): below. A special case seems to be the trapezium cluster in - 01 16:  Tucanae, the Orion. While data for the brighter pairs - 01 32: I 264 AB in Eridanus, combining A, B, C, and D more or less agree with re- - 01 40: DUN 5 (p) Eridani, cent entries in the WDS (the most recent ones are from - 19 19: I 253 in Sagittarius, 2013), the positions of E and F significantly deviate - 19 28: SCJ 22 (BU 142) in Sagittarius, from older data. However, because of the unknown error - 20 01: HDO 294 in Sagittarius, margins, no definite conclusions as to individual move- - 20 29:  Capricorni, ments can be drawn so far. See also Figure 4. 2 - 20 39:  Capricorni The error margins of measurements of the position 2 angle are expected to be of the order of about +/- 0.2 - 22 55:  Gruis. degrees for large separations, but to increase towards small separations, and can reach several degrees for very Some images of double and multiple systems are close pairs. The reason is the fixed resolution in the im- presented in the following figures. Figure 3 is a selec- ages. In fact, this is apparent in the plots in fig. 2. How- tion of close binaries with sub-arcsec separations. (Continued on page 239)

Figure 3. A selection of close binaries. 50 cm RC telescope. Image of JC 8 is overexposed and inverted in order to better show the dim companion C. See also notes 20 39, 19 19, 19 02, 01 06, 03 12, and 05 08, respectively. North is down, and east is right, as in all images.

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Figure 4. The trapezium cluster in Orion. 50cm RC. Superposi- Figure 5. ACRUX: Superposition of a 2sec exposure and a short- tion of three images with different exposure times (~300 frames er exposure (as negative). Brightness of component G is estimat- each with 20 msec, 100 msec, and 1 sec). The contrast was ed to about 10 mag. Even dimmer companions H and I are only strongly enhanced, and partly reversed, so as to reveal both the seen with strongly enhanced contrast. See also note 12 27. relative positions of the brighter stars as well as of the dimmer ones. Components as listed in the WDS are indicated. Brightness of G is given as 16.7 mag. The one second image also shows parts of the and several field stars. See text.

Figure 6. Plots of position angle (left) and separation (right) of the pair HDO 294 vs. date. Rhombs are speckle data, crossed circles are own measurements. Curves indicate the currently assumed ephemeris. See also note 20 01.

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(Continued from page 237) Conclusion For many of the doubles investigated here, there are only few data found in the literature, and often with large scatter, although most systems are fairly bright, and easily accessible. The accuracy of my own measure- ments is checked by comparing with mainly speckle data of systems, which have frequently been observed. Generally, the scatter is of comparable magnitude. As in earlier work, this measuring campaign again revealed several double star systems, which should be measured more often. References [1] IAS, http://www.ias-observatory.org [2] Anton, R., 2010, Journal of Double Star Observa- tions, vol. 6 (2), 133-140. [3] Anton, R., 2012, Lucky imaging. In Observing and Measuring Visual Double Stars, 2nd Edition, Robert Argyle, ed., Springer, New York. [4] Mason, B.D. et al., The Washington Double Star Catalog (WDS), U.S. Naval Observatory, online access Feb. 2014. [5] Hartkopf, W.I. et al., Fourth Catalog of Interferomet- ric Measurements of Binary Stars, U.S. Naval Ob- servatory, online access Feb. 2014. [6] Hartkopf, W.I. et al., Sixth Catalog of Orbits of Vis- ual Binary Stars, U.S. Naval Observatory, online access Feb. 2014. [7] Burnham´s Celestial Handbook, R. Burnham, Jr., Dover Publications, New York 1978.

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Discovery of Stellar Duplicity of TYC 1950-02320-1 During Asteroidal Occultation by (141) Lumen

Japan Mitsuru Sôma ([email protected]) and Tsutomu Hayamizu, IOTA Japanese Coordinators. M. Ishida; M. Owada; M. Ida; R. Aikawa, A. Hashimoto, T. Horaguchi, K. Kitazaki, S. Uchiyama, S. Uehara, and A. Yaeza; observers

USA Brad Timerson, IOTA North American Coordinator; T. George, W. Morgan; observers

Netherlands E. Edens, (observed from USA)

Abstract: An occultation of TYC 1950-02320-1 by the (141) Lumen on 2013 Decem- ber 28 showed this star to be a double star. Both components of the double star were occulted as recorded by one observer, one component of the double star was occulted by three observers, and 9 observers recorded miss observations. The separation of the two components is 0.1529 ± 0.0008 arcseconds at a position angle of 105.8 ± 0.7 degrees. The magnitude of the primary component is estimated to be 11.25 (V). The magnitude of the secondary component is estimat- ed to be 11.47 (V).

Tycho system magnitudes VT and BT given in the Ty- Observation cho-2 Catalogue. The asteroid magnitude as predicted On 2013 December 28, thirteen observers occupy- by the Center using the magnitude param- ing or operating sites across the United States and Ja- eter values H = 8.4 and G = 0.15 was 12.54 (V). The pan observed the asteroid (141) Lumen occult the star combined magnitude of the asteroid and the star was TYC 1950-02320-1. See Figure 1 for the path map of calculated to be 10.43 (V). The expected magnitude the event. One site in Arizona, USA (George) observed drop at occultation was calculated to be 2.11 magni- two-separate drops in brightness, neither of which had tudes. The star is not listed in the Fourth Interferomet- a mag drop as large as predicted, indicating a double ric Catalog, nor is it listed in the Washington Double star (see Figure 2). Three sites in Japan (Ishida; Owa- Star Catalog. da; Ida) had only a single drop in brightness (see Fig- ures 3, 4, and 5). For these latter sites, the magnitude Analysis drop measured was consistent with observation of the The observations were analysed in the standard secondary star only. Nine sites had a miss. All record- manner described by IOTA [1]. ed occultation times and data from the observers can be The finished plot of the double star fit to the data is found in archived IOTA records for the event. The shown in Figure 6. The double star has a separation of observations were made by the observers located at the 0.1529 ± 0.0008 arcseconds at a position angle of 105.8 sites and with the equipment shown in Table 1. ± 0.7 degrees. Of the data sets that recorded the occul- The target star is magnitude 10.60 ± 0.09. This is a (Continued on page 243) V magnitude in the Johnson system derived from the

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Discovery of Stellar Duplicity of TYC 1950-02320-1 During Asteroidal Occultation by (141) Lumen

Figure 1. Occultation Path

Figure 2. George light curve showing two distinct events

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Discovery of Stellar Duplicity of TYC 1950-02320-1 During Asteroidal Occultation by (141) Lumen

Figure 3. Ishida light curve

Figure 4 – Owada light curve

Figure 5 -- Ida light curve

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Discovery of Stellar Duplicity of TYC 1950-02320-1 During Asteroidal Occultation by (141) Lumen

Table 1. Observers, site locations, equipment, methods, and results

Figure 6 State Telescope Telescope Observer Location Country Method Result Chords Prefecture Type Dia (cm) Video + 1 E. Edens Magdalena NM USA/Holland SCT 15 Miss GPS Time Inst Visual + 2 A. Yaeza Hitachi Ibaraki Japan SCT 20 Miss Stop Watch Visual + 3 A. Hashimoto Chichibu Saitama Japan SCT 40 Miss Stop Watch Video + 4 W. Morgan Pleasanton CA USA SCT 20 Miss GPS Time Inst Visual + 5 R. Aikawa Sakado Saitama Japan SCT 20 Miss Stop Watch Video + 6 T. Horaguchi Tsukuba Ibaraki Japan Reflector 50 Miss GPS Time Inst Visual + 7 S. Uehara Tsukuba Ibaraki Japan Reflector 20 Miss Stop Watch Video + 8 S. Uchiyama Kashiwa Chiba Japan SCT 25 Miss GPS Time Inst Video + 9 K. Kitazaki Musashino Tokyo Japan Cass 40 Miss GPS Time Inst Video + 11 M. Ida Odai Mie Japan SCT 20 One Event GPS Time Inst Video + 12 M. Owada Hamamatsu Shizuoka Japan SCT 25 One Event GPS Time Inst Video + 13 M. Ishida Taiki Mie Japan SCT 20 One Event GPS Time Inst Video + 14,15 T. George Scottsdale AZ USA SCT 30 Two Events GPS Time Inst Based on the average magnitude drop estimates for (Continued from page 240) the two components shown in Table 2, the combined tation, George recorded both events with magnitude magnitude of each component star + asteroid was calcu- drops suitable for calculating the stellar component lated. The magnitudes of the two component stars were magnitudes. Using the light curve data from all observ- derived by adjusting for the brightness of the asteroid in ers, the magnitude drops of the two events were calcu- the light curve. The magnitudes of the two stars are es- lated using the brightness measurements derived by R- timated to be 11.25 ± 0.1 (V) primary star and 11.47 ± OTE [2], the Magnitude calculator routine in Occult4 0.1 (V) secondary star, and their magnitude difference is [3] (Method 3 – Magnitudes from light curve values), estimated to be 0.22 ± 0.06 (V). The event was a the combined V magnitude from the Tych-2 Catalogue BBAA, with the secondary occulted first, then the pri- and the predicted V magnitude of the asteroid as ex- mary. plained above. The results are shown in Table 2. Note Based on the data presented in this report, the dou- that the measured magnitude drops are instrumental ble star characteristics as shown in the plot in Figure 6 magnitudes with no filters, and we assume that they are are: not much different from those in V in calculating the Star TYCHO 1950-02320-1 magnitude of each component of the double star. UCAC2 39846549 UCAC4 563-047083 NOMAD 1125-0200778 PPMXL 4181982505129551400 Table 2 – Calculated magnitude drops Spectral type F5III [4] Coordinates (UCAC4) RA 09h 05m 39.2553s Observer 1st Event 2nd Event Dec +22° 34' 52.828" George 0.56 ± 0.03 0.69 ± 0.03 (ICRS(J2000), Epoch 2013 Dec 28) Mag A 11.25 ± 0.1 (Est. Tycho-2 V mag) Owada 0.52 ± 0.02 Mag B 11.47 ± 0.1 (Est. Tycho-2 V mag) Mag Difference 0.22 ± 0.06 Ida 0.49 ± 0.03 Separation 0.1529 ± 0.0008 arcseconds Ishida 0.51 ± 0.03 Position Angle 105.8 ± 0.7 degrees

Average 0.52 ± 0.02 0.69 ± 0.03

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Figure 6. Occultation of TYC 1950-02320-1 by (141) Lumen

References 1. Herald, David, "New Double Stars from Asteroidal Occultations, 1971 – 2008", JDSO, 6, 88-96, 2010. 2. ROTE – R-Code Occultation Timing Extractor – Presentation at the 2013 Annual IOTA Meeting, October 4-6, 2013; Toronto, Ontario, Canada. http://www.asteroidoccultation.com/observations/ NA/2013Meeting/R-OTE%202013%20IOTA% 20Conference.pdf 3. Occult v4.1.0. Occultation prediction software by David Herald. http://www.lunar-occultations.com/ iota/occult4.htm 4. Pickles, A. and E. Depagne, “All-Sky Spectrally Matched UBVRI – ZY and u’g’r’i’z’ Magnitudes for Stars in the Tycho2 Catalog” , PASP, 122, 1437- 1464, 2010.

Vol. 10 No. 3 July 1, 2014 Journal of Double Star Observations Page 245

Second Annual Apple Valley Double Star Workshop

High Desert Astronomical Society

July 26 – 27, 2014 Luz Observatory

The Lewis Center for Educational Research 20702 Thunderbird Rd. Apple Valley, CA. 923907

Workshop Co-Chairs Mark Brewer, California State University, San Bernardino High Desert Astronomical Society

Sean Gillette, Vanguard Preparatory School

William Buehlman, California State Polytechnic University, Pomona

Reed Estrada, Central Coast Astronomical Society

Chris Estrada, California State University, Los Angeles, Central Coast Astronomical Society

Eric Weise, California State University, San Diego

Vol. 10 No. 3 July 1, 2014 Journal of Double Star Observations Page 246

Apple Valley Double Star Workshop

Local Host High Desert Astronomical Society Schedule

Saturday July 26, 2013 Scheduled Participants from California Polytechnic State University 4:00pm – 6:00pm: Telescope set up California State University, San Diego 6:00pm – 6:15pm: Meet and Greet 6:15pm – 6:30pm: Introduction California State University, San Bernardino 6:30pm – 7:00pm: Dinner Vanguard Preparatory School 7:00pm – 7:15pm: Group Picture Victor Valley College 7:15pm – 8:00pm: Team meetings High Desert Astronomical Society 8:00pm – 10:00pm: Observations* Central Coast Astronomical Society Sunday July 27, 2013

Workshop participants will measure the separa- 9:00am – 12:00pm: Reductions/Presentation/Writing 12:00pm – 12:30pm: Lunch tion and position of a double star. Participants will 12:30pm – 12:45pm: Group 1 Presents use varying methods where they write up their re- 12:45pm – 1:00pm: Group 2 Presents sults and compare them among other workshop par- 1:00pm – 1:15pm: Group 3 Presents ticipants. Participants will have their papers pub- 1:15pm – 1:30pm: Group 4 Presents lished within the Journal of Double Star Observa- 1:30pm – 1:45pm: Group 5 Presents 1:45pm – 2:00pm: Group 6 Presents tions. 2:00pm –Workshop Adjourned Please R.S.V.P. via email at: [email protected] Recommended Hotel Hawthorne Suites 11750 Dunia Road Victorville, CA 92392

*Weather permitting

Participants of the first Apple Valley Workshop.

Vol. 10 No. 3 July 1, 2014 Journal of Double Star Observations Page 247

2014 Lowell Speckle Interferometry Workshop

Friday-Sunday, October 3-5, 2014 Giclas Lecture Hall, Lowell Observatory, Flagstaff, AZ, USA

Workshop co-chairs: Gerard van Belle, Lowell Observatory Russell Genet, California Polytechnic State University

Overview Speckle interferometry, once the sole province of professional astronomers, has expanded to in- clude many amateur and undergraduate and even high school student observers and analysts. This ex- pansion is due to the increased availability of high-speed CCD cameras, powerful PCs, PC-friendly soft- ware, and opportunities for publication. Speckle interferometry overcomes normal atmospheric seeing conditions by taking a series (often thousands) of short-exposure images (typically 10-60 milli-seconds) which “freeze out” the usual atmos- pheric smearing. Speckle interferometry only works within the isoplanatic patch where atmospheric dis- tortions are correlated—typically less than 10 arc seconds. Analyzing speckle images works best when observing geometrically simple objects such as close visual double stars, binary , Pluto and Charon, Jupiter’s moons, and the diameters of large nearby stars. The Lowell Speckle Interferometry Workshop brings professional, amateur, and student astrono- mers together in a synergistic mix that aims to consider science programs, speckle observations, data re- duction, and analysis in a hands-on, informal atmosphere. The workshop will feature, weather permitting, speckle interferometry observations on Lowell Observatory’s 4.3-meter Discovery Channel Telescope in nearby Happy Jack. We will be using the Dif- ferential Speckle Survey Instrument (DSSI) developed by Elliott Horch. DSSI features simultaneous ob- servations in two color bands and two Andor iXon EMCCD cameras.

Schedule

Friday, October 3 Morning: free time Afternoon: Theory of speckle interferometry Evening: at Lowell Observatory Rotunda patio; all portable equipment set-ups are welcome

Saturday, October 4 Morning: free time Afternoon: Science applications of speckle Binary stars Binary asteroids Pluto & Charon / Jupiter’s moons Resolved stellar disks Evening: at 4.3-meter Discovery Channel Telescope with DSSI

Sunday, October 5 Morning: free time Afternoon: Data reduction workshop using observations from previous 2 nights Evening: Banquet

Vol. 10 No. 3 July 1, 2014 Journal of Double Star Observations Page 248

Journal of Double Star Observations The Journal of Double Star Observations (JDSO) pub- July 1, 2014 lishes articles on any and all aspects of astronomy involv- Volume 10, Number 3 ing double and binary stars. The JDSO is especially in- terested 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 Russ Genet by an amateur astronomer will be reviewed by other ama- Justin Sanders teur astronomers doing similar work.

Assistant Editors Not all articles will undergo a peer review. Articles Jo Johnson that are of more general interest but that have little new Vera Wallen scientific content such as articles generally describing double stars, observing sessions, star parties, etc. will not Student Assistant Editor be refereed. Eric Weise Submitted manuscripts must be original, unpublished Advisory Editors Brian D. Mason material and written in English. They should contain an William I. Hartkopf abstract and a short description or biography (2 or 3 sen- tences) of the author(s). For more information about for- Web Master mat of submitted articles, please see our web site at Michael Boleman http://www.jdso.org

Submissions should be made electronically via e-mail The Journal of Double Star Observations is to [email protected] or to [email protected]. an electronic journal published quarterly. Articles should be attached to the email in Microsoft Copies can be freely downloaded from Word, Word Perfect, Open Office, or text format. All http://www.jdso.org. images should be in jpg or fits format.

No part of this issue may be sold or used in commercial products without written permis- sion of the Journal of Double Star Observa- tions.

©2014 Journal of Double Star Observations

Questions, comments, or submissions may be directed to [email protected] or to [email protected]

We’re on the web!

http://www.jdso.org