THE MINOR PLANET

BULLETIN OF THE MINOR PLANETS SECTION OF THE BULLETIN ASSOCIATION OF LUNAR AND PLANETARY OBSERVERS

VOLUME 34, NUMBER 2, A.D. 2007 APRIL-JUNE 27.

THE ROTATION PERIOD OF 2651 KAREN

Colin Bembrick Mt Tarana Observatory PO Box 1537, Bathurst, NSW 2795, Australia [email protected]

Bill Allen Vintage Lane Observatory 83 Vintage Lane, RD3, Blenheim, New Zealand

(Received: 6 January)

2651 Karen was observed over 4 nights in 2006. The synodic period was determined as 6.3227 ± 0.0037 hr. The peak to peak amplitude was approximately 0.3 mag, implying an axial ratio (a/b) of 1.32 References Bembrick, C.S., Richards, T., Bolt, G., Pereghy, B., Higgins, D. Minor planet 2651 Karen (1949 QD) was discovered by E. and Allen, W.H. (2004). “172 Baucis – A Slow Rotator”. Minor Johnson in August 1949 at Johannesburg. This is an outer main Planet Bulletin, 31, 51-52. belt asteroid with a diameter of 39.7 km (GUIDE ver 8). The latest list of rotational parameters (Harris & Warner, 2006) has no GUIDE version 8 (2002). http://www.projectpluto.com quoted period. Harris, A.W. and Warner, B.D. (2006). “Minor Planet Lightcurve The observations of Karen in 2006 were conducted from two sites Parameters”. Updated March 14, 2006. – one in New Zealand and one in Australia. The locations of these http://cfa-www.harvard.edu/iau/lists/LightcurveDat.html sites are listed in Bembrick et al (2004). All observations were made using unfiltered differential photometry and all data were Harris, A.W., Young, J.W., Bowell, E., Martin, L. J., Millis, R. L., light time corrected. The aspect data (Table I) also shows the Poutanen, M., Scaltriti, F., Zappala, V., Schober, H. J.,Debehogne, percentage of the light curve observed each night. PAB is the H, and Zeigler, K. (1989). “Photoelectric Observations of Phase Angle Bisector. Asteroids 3, 24, 60, 261, and 863.” Icarus 77, 171-186.

Period analysis was carried out using the “Peranso” software Vanmunster, T. (2006). Peranso ver 2.0. http://www.peranso.com (Vanmunster 2006). Various routines available in Peranso were utilised, including the “FALC” routine based on Harris et al (1989). Due to the noisy lightcurve and the relatively short observing span, a definitive period was not obvious. The derived period appears to be the best fit to the data, but other periods at 12.7 and 9.5 hours cannot be ruled out entirely. The final analysis UT Date PAB PAB Phase %Phase determined a period of 6.3227 ± 0.0037 hr which was used to Long Lat Angle Coverage 2006 Oct 26 32.6 -25.6 15.8 38 compile the composite light curve with the arbitrary zero phase 2006 Oct 27 32.7 -25.7 15.9 49 maximum at JD 2454034.666 (see Figure 1). The peak to peak 2006 Oct 30 33.0 -25.6 16.0 47 variation in the lightcurve implies an axial ratio (a/b) of 1.32. Full 2006 Nov 09 34.2 -25.4 17.2 110 phase coverage was achieved but the noisy light curve could bear checking. Table I. Aspect data for Karen in 2006.

Minor Planet Bulletin 34 (2007) Available on line http://www.minorplanetobserver.com/mpb/default.htm 28

FIRST PERIOD DETERMINATION FOR Finally, we should mention a third possible solution of 9.72 ± 0.01 ASTEROID 1564 SRBIJA hr. This solution has just slightly larger RMS uncertainty than the preceding two, and it does not exhibit the bimodal shape. Maryanne Angliongto and Milan Mijic Interestingly enough, there is only a moderately weak signal at Department of Physics and Astronomy twice the period, but much stronger local minima in the noise California State University, Los Angeles spectrum at three times the period, or 29 hours. We suspect that 5151 State University Dr., Los Angeles, CA 90032 this solution is likely an alias, but we cannot be certain of that. [email protected], [email protected] More data is needed to verify these findings. For now, we may (Received: 2 December) adopt the 29.64 ± 0.02 hr as the tentative value for the period. This lightcurve is displayed in Figure 1. The estimated amplitude is 0.38 ± 0.02 mag, consistent for all three solutions. Lightcurve measurement of 1564 Srbija performed April – June 2006 yielded a tentative synodic rotation period Acknowledgements of 29.64 ± 0.02 hr. We would like to thank Jim Young and Ron Wodaski for their assistance during the observing sessions at TMO and BBO, Our observations of 1564 Srbija were carried out at three respectively, and Brian Warner for his helpful and timely locations: 3 nights at JPL Table Mountain Observatory (TMO) in responses to questions related to Canopus. Wrightwood, CA; 4 nights at Blackbird Observatory (BBO) in Cloudcroft, NM; and 2 nights at El Dorado Hills Observatory References (EDHO) in El Dorado Hills, CA. In total, we had 15 sessions with 95 data points. The table shows the observation dates for each Harris, A. W., Young, J. W., Bowell, E., Martin, L. J., Millis, observatory, equipment used, bands measured, and range of R.L., Poutanen, M., Scaltriti, F., Zappala, V., Schober, H. J., observed phase angle. All images were dark subtracted and flat- Debehogne, H., and Zeigler, K. W. (1989). “Photoelectric fielded before measuring using MPO Canopus by Bdw Publishing. Observations of Asteroids 3, 24, 60, 261, and 863.” Icarus 77, 171-186. We used MPO Canopus for differential aperture photometry of all images. Data were corrected by light travel time from the asteroid to the Earth, and times are for mid-exposure. Adjustments were made to the differential magnitudes in order to eliminate causes of magnitude fluctuation not related to the rotation, such as changing observing conditions and phase angle between nights. We also used Canopus to determine the period, using a Fourier analysis routine written by Alan Harris (1989).

At the time of observation, the asteroid was of magnitude 16.5- 17.3, and it was a few months after opposition, setting by midnight or earlier. It was a particularly difficult target for the 0.3m EDHO telescope with the resulting low signal causing an excessively large magnitude error. The minimal proper motion of the asteroid on May 26 enabled us to increase the signal by adding consecutive images in groups of three, thus decreasing the error. We could not use this technique with the June 26 EDHO data, so we did not include them in the period determination. This brings our data set down to 85 points, with only slight changes in values for the period, but within the formal uncertainty of the harmonic analysis.

The value of 29.64 ± 0.02 hr emerged as the preferred rotation Figure 1. The lightcurve of 1564 Srbija phased to a period of period, characterized by the classical bimodal shape of the 29.64 hrs. lightcurve, low RMS deviation between observed and modeled magnitudes, and strong signal at half-period of 14.79 ±0.01 hours. The next strongest period candidate is 18.29 ± 0.01 hr. The secondary minimum appears to be much shallower, but we cannot be certain of that since our data coverage is very sparse in that region. This solution also has a moderately strong signal at half the period.

Dates (2006) Location Telescope Camera Band Phase Angle April 25, May 3, 17 TMO 0.6m f/16 1024x1024 24µm B,V,R 6.3 - 11.6 May 25, 27, 29, 30 BBO 0.5m f/8.3 R-C SBIG STL-11000 C,Red 12.9 - 13.7 May 26, June 26 EDHO 0.3m LX200 f/4 SBIG ST-7 R 13.1 - 15.6 Table 1.

Minor Planet Bulletin 34 (2007) 29

LIGHTCURVE OF MINOR PLANET 2006RZ photometric studies. Thanks also to Ellen Howell and Mike Nolan at Arecibo Observatory for their assistance and openness. Gary A. Vander Haagen Stonegate Observatory References 825 Stonegate Road, Ann Arbor, MI 48103 [email protected] Harris, A.W., Young, J.W., Bowell, E., Martin, L.J., Millis, R.L., Poutanen, M., Scaltriti, F., Zappala, V., Schober, H.J., Debehogne, (Received: 16 November) H., and Zeigler, K.W., (1989). “Photoelectric Observations of Asteroids 3, 24, 60, 261, and 863.” Icarus 77, 171-186.

Analysis of lightcurves of 2006 RZ spanning 10 days Nolan, M., (2006). “Scheduled Arecibo Radar Asteroid from September 25, 2006 through October 4, 2006 with Observations, Future Observations”. http://www.naic.edu/ 973 data points produced an indeterminate rotation ~pradar/sched.shtml period. The most prominent periods were 4.967 hrs and 5.540 hrs with an amplitude of 0.20 ± 0.04 mag. Vannmunster, T. (2006), Peranso Period Analysis Software, Astrometric data was also submitted to the Minor Planet Peranso version 2.10, CBABelgium, http://users.skynet.be/ Center for the same time period. fa079980/peranso/index.htm

Warner, B.D. (2006). MPO Software, Canopus version 9.2.0.0, Minor Planet 2006 RZ was listed as a radar target for Arecibo Bdw Publishing, http://minorplanetobserver.com/ (Nolan 2006) requesting astrometric and photometric data prior to the targeting dates of October 1, 7, and 9, 2006. Astrometric and photometric data were collected using a 36 cm Celestron C-14, a SBIG ST-10XME camera, and clear filter at Stonegate Observatory. The image scale was 1.4 arc-seconds per pixel and camera temperature held at –15C for all measurements. All images were collected unguided.

Data were collected on every available clear night from September 25 through October 4, 2006, resulting in 9 data sets. 2006 RZ ranged from 2 arc-second/minute sky motion and 17th mag. to 20 arc-seconds/min and 14.7 mag. on October 4, 2006. Exposures ranged from 60 seconds to 10 seconds. It presented a challenge to maintain a S/N above 25 due to the combination of faint magnitude, image scale, and fast movement of the object.

Clouds and numerous weather interruptions occurred during the data collection period. Of the 9 data sets, 4 were of less than one hour with the balance ranging between 1.5 and 5.7 hours. In all, 973 data points were collected. The photometric data were collected using MPO Canopus (Warner 2006). With assistance 2006RZ Photometric Data Phased to 5.540 hours from Brian Warner in analyzing the noisy data, a probable solution of 5.530 ± 0.020 hours was found. The photometric noise of 0.02 to 0.08 magnitudes created difficulty in matching the data set amplitudes and obtaining high probability solutions.

The data were also analyzed using Peranso version 2.10 (Vannmunster 2006) using the FALC (Harris 1989) method. Multiple period solutions were identified at 4.967, 5.180, 5.366, and 5.540 hours with the most predominate yet inconclusive at 5.540 hours. Data sets with the noisiest data were also reanalyzed to reduce noise where possible through selection of alternate reference stars and close attention to positions of the minor planet to other bright objects during the photometric reduction. However, there were still insufficient data with long enough runs and sufficient S/N to yield a high probability period solution. In personal email notes with both Ellen Howell and Petr Pravec, this range of periods is consistent with the radar data collected at the Arecibo Observatory during the cited October 1-9, 2006 2006RZ Photometric Data Phased to 4.967 hours investigation.

Acknowledgments

The author appreciates the help from Brian Warner on Canopus period analysis and his continued encouragement on asteroid

Minor Planet Bulletin 34 (2007) 30

ASTERIOD LIGHTCURVE ANALYSIS OF 554 PERAGA

David Higgins Hunters Hill Observatory (E14) 7 Mawalan Street Ngunnawal ACT 2913, Australia [email protected]

Brian D. Warner Palmer Divide Observatory Colorado Springs, CO 80908

Roger Dymock Director, Asteroids and Remote Planets Section British Astronomical Association Acknowledgements Martin Crow Crayford Manor House Astronomical Society The SBIG ST-8E used by Hunters Hill was funded by The Kent, UK Planetary Society under the 2005 Gene Shoemaker NEO Grants program. (Received: 24 December) References

The main belt asteroid 554 Peraga was observed by the Higgins, D. (2005). “Asteroid Lightcurve Analysis at Hunters Hill authors in support of radar observations. Data analysis Observatory and Collaborating Stations - Autumn/Winter 2005”, produced a lightcurve with a synodic period of 13.7128 Minor Planet Bulletin 33, 8-11. ± 0.0003 hrs and amplitude of 0.20 ± 0.02 mag. Scaltriti, F. and Zappala, V. (1979). Icarus 39, 124-130. Observations of 554 Peraga were requested by Dr. Ellen Howell of Stephens, R. D. (2007). “Asteroid Lightcurve Photometry from Arecibo to support radar observations. The target was also Santana and GMARS Observatories – September-December observed by Roger Dymock and Martin Crow from the UK who 2006”. MPB 32, 31 obtained a period of 13.715hrs from their own data and additional data were obtained by Brian Warner of Palmer Divide Warner, B.D. (2006). CALL website, Observatory, Colorado Springs, USA. The previous published data http://www.minorplanetobserver.com/astlc/default.htm. for this target indicated a period of 13.68 hrs (Scaltriti 1979).

Hunters Hill Observatory is equipped as described in Higgins (2005). All observations for this paper were made using a clear Observer Sessions (see plot) filter with guided exposure times ranging from 120 seconds to 240 seconds. MaxIm DL/CCD, driven by ACP4, was used for Higgins 181, 182, 189, 194, 196, 199, 204, 207 telescope and camera control whilst calibration and image Dymock 221 measurements were undertaken by MPO Canopus version 9. Crow 222, 224, 225, 226, 227, 228, 229, 230 Palmer Divide Observatory, run by Brian D Warner, used a 0.35m SCT at f/9.1 and a FLI IMG-1001E CCD producing a scale of 2.5 Warner 219, 220 arcseconds/pixel. Exposures were limited to 90 seconds. Roger Table I. Observation sessions by observer. Dymock used a 0.25 m, f/6.4 Newtonian on a German equatorial mount with a Starlight Xpress MX516 CCD camera attached. Martin Crow used an 0.25 m, f/10 SCT with a Starlight Xpress MX916 attached. Table I shows which observations were contributed by each observer.

Analysis of the combined data set showed yielded a synodic rotation period of 13.7128 ± 0.0003 hrs. The amplitude of the curve was 0.20 ± 0.02 mag. The results reported here are in agreement with those reported by Stephens (2007).

Howell was able to obtain data from radar observations at Arecibo. All the data obtained in this observing campaign have been sent to Howell to assist with the interpretation of that radar data. Early indications are of an unusual shape for such a large Main Belt asteroid. Howell’s data and interpretation will be published separately.

Minor Planet Bulletin 34 (2007) 31

ASTEROID LIGHTCURVE PHOTOMETRY FROM 554 Peraga. This target was selected because of a request for SANTANA AND GMARS OBSERVATORIES – lightcurve observations from Ellen Howell to support radar SEPTEMBER TO DECEMBER 2006 observations and IR spectroscopy. The results reported here are in agreement with those reported by Higgens et al. (2007). Robert D. Stephens 11355 Mount Johnson Court 3279 Solon. Observations were initially obtained with Santana’s Rancho Cucamonga, CA 91737 USA 0.3m telescope in suburban city skies. Shortly thereafter the target [email protected] was added to the Binary Asteroid Survey. Additional observations were obtained from GMARS on November 25 and 26 using the (Received: 27 December) Meade 0.35m RCX400.

3773 Smithsonian. Observations were initially obtained with Lightcurve period and amplitude results from Santana Santana’s 0.3m telescope in suburban city skies. Shortly and GMARS Observatories are reported for 2006 thereafter the target was added to the Binary Asteroid Survey September-December: (Pravec 2005). Additional observations were obtained from 554 Peraga (13.71 ± 0.01 hr and 0.28 mag), GMARS on September 23 and 24 using the 0.35m Celestron. 2215 Sichuan (3.975 ± 0.001 hr and 0.40 mag), 3279 Solon (8.10 ± 0.01 hr and 0.85 mag), Acknowledgements 3773 Smithsonian (6.9804 ± 0.0001 hr and 1.04 mag). Thanks are given to Dr. Alan Harris of the Space Science Institute, Boulder, CO, and Dr. Petr Pravec of the Astronomical Institute, The author operates telescopes at two observatories. Santana Czech Republic, for their ongoing support of all amateur asteroid. Observatory (MPC Code 646) is located in Rancho Cucamonga, Also, thanks to Brian Warner for his continuing work and California at an elevation of 400 meters and contains a Meade enhancements to the software program “Canopus” which makes it 0.3m RCX400 telescope. GMARS (Goat Mountain Astronomical possible for amateur astronomers to analyze and collaborate on Research Station, MPC G79) is located at the Riverside asteroid rotational period projects and for maintaining the CALL Astronomical Society’s observing site at an elevation of 879 Web site which helps coordinate collaborative projects between meters and contains several observatories. The author’s amateur astronomers. observatories at GMARS contains a Celestron 0.35m mounted on a Paramount from Software Bisque and a Meade 0.35m RCX400 References telescope. All observations were obtained with an SBIG ST1001 CCD camera with the image scale of approximately 2.2 Harris, A. W., Warner, B. D. (2006). http://www.minorplanet arcseconds per pixel at Santana Observatory and 2.4 arcseconds observer.com/astlc/LC.zip. per pixel at GMARS. Further details of the equipment used can be found at the author’s web site: Higgins, D., Warner, B. D., Dymock, R., and Crow, M. (2007). http://members.dslextreme.com/users/rstephens/. “Asteroid Lightcurve Analysis of 554 Peraga”. MPB 32, 30

Unless otherwise noted, all observations were obtained from Pravec, P. (2005). “Photometric Survey of Asynchronous Binary Santana Observatory. Most targets were chosen from the list of Asteroids”. asteroid photometry opportunities published by Brian Warner and http://www.asu.cas.cz/~asteroid/binaryphotosurvey.htm Alan Harris on the Collaborative Asteroid Lightcurve Link (CALL) website (Harris 2006). The images were measured and Stephens, R.D. (2006). http://members.dslextreme.com/ period analysis was done using the software program MPO users/rstephens/. Canopus which uses differential aperture photometry to determine the values used for analysis.

The results are summarized in the table below. Column 2 gives the dates over which the observations were made. Column 3 gives the number of observations used. Column 4 is the range of phase angles over the full data range. If there are three values in the column, this means the phase angle reached a minimum with the middle valued being the minimum. Columns 5 and 6 give the range of values for the Phase Angle Bisector (PAB) longitude and latitude respectively. Column 7 gives the period and column 8 gives the error in hours. Columns 9 and 10 give the amplitude and error in magnitudes.

Asteroid Dates Data Phase LPAB BPAB Per PE Amp AE (2006) Points (h) 554 Peraga 09/27–10/05 1,005 13.4, 9.5 25.7, 26.4 4.1, 4.2 13.71 0.01 0.28 0.03 2215 Sichuan 12/01–08 395 1.4, 0.2, 2.6 71.1, 71.5 -0.2, 0.4 3.975 0.001 0.40 0.03 3279 Solon 11/19–26 398 2.2, 4.8 56.7, 57.1 -3.3, -3.4 8.10 0.01 0.85 0.03 3773 Smithsonian 09/13-24 1,112 10.2, 3.1 3.1, 4.4 -1.9 6.9804 0.0001 1.04 0.02 Table I: Observation Results

Minor Planet Bulletin 34 (2007) 32

ASTEROID LIGHTCURVE ANALYSIS AT telescopes/camera combinations was used: 0.5m Ritchey- THE PALMER DIVIDE OBSERVATORY – Chretien/FLI IMG-1001E, 0.35m SCT/FLI IMG-1001E, 0.35m SEPTEMBER-DECEMBER 2006 SCT/ST-9E , or 0.35m SCT/STL-1001E. The scale for each was about 2.5 arcseconds/pixel. Exposure times were 60–240s. All but Brian D. Warner the 0.35m/FLI-1001E were guided. The operating temperature for Palmer Divide Observatory/Space Science Institute the FLI and STL-1001E was–30°C. The ST-9E was run at –10°C. 17995 Bakers Farm Rd., Colorado Springs, CO 80908 [email protected] All images were measured using MPO Canopus, which employs differential aperture photometry to determine the values used for (Received: 8 January) analysis. Period analysis was also done with Canopus, incorporating the Fourier analysis algorithm developed by Harris (1989). Lightcurves for 25 asteroids were obtained at the Palmer Divide Observatory from late September through The results are summarized in the table below and individual plots December 2006: 143 Adria, 469 Argentina, 595 are presented. The data and lightcurves are presented without Polyxena, 880 Herba, 1515 Perrotin, 1756 Giacobini, comment except when warranted. Column 3 gives the full range of 1920 Sarmiento, 2645 Daphne Plane, 2793 Valdaj, 4125 observation dates; column 4 gives the number of data points used Lew Allen, 4142 Derzu-Uzala, 4690 Strasbourg, 4860 in the analysis. Column 5 gives the range of phase angles. If there Gubbio, 6794 Masuisakura, (10171) 1995 EE8, 13025 are three values in the column, the phase angle reached a Zurich, (15786) 1993 RS, 17681 Tweedledum, (24827) minimum with the middle value being the minimum. Columns 6 1995 RA, (30019) 2000 DD, (31180) 1997 YX3, and 7 give the range of values (or average if the range was (31354) 1998 TR3, (32814) 1990 XZ, (34817) 2001 relatively small) for the Phase Angle Bisector (PAB) longitude SE116, and 2006 WH1. and latitude respectively. Columns 8 and 10 give the period and amplitude of the lightcurve while columns 9 and 11 give the Observations of 25 asteroids were made at the Palmer Divide respective errors in hour and magnitudes. An "(H)" follows the Observatory from June through September 2006. One of four Minor Planet Bulletin 34 (2007) 33

Date Range Data Per Amp (mm/dd) # Name Pts Phase L B (h) PE (m) AE 2006 PAB PAB 143 Adria 12/04-10 763 10.1-11.7 48.5 13.7 21.89 0.02 0.10 0.01 469 Argentina 11/09-19 1434 7.2-5.2 63.1 14.0 17.573 0.003 0.12 0.02 595 Polyxena 12/05-10 893 7.1-8.5 55.3 12.4 15.89 0.01 0.05 0.01 880 Herba 11/17-23 604 5.7-4.4 60.0 8.5 12.215 0.004 0.21 0.02 1515 Perrotin 11/27-12/10 313 11.2-17.6 48.0 1.5 13.965 0.002 0.19 0.02 1756 Giacobini 12/11-15 486 2.4-2.9 79.6 3.8 3.8527 0.0005 0.21 0.02 1920 Sarmiento (H) 10/30-11/09 152 18.3-10.8 59.5 -7.5 4.0501 0.0004 0.28 0.02 2645 Daphne Plane 12/12-19 309 13.7-15.9 64.4 18.7 8.360 0.003 0.09 0.01 2793 Valdaj 12/13-22 244 11.4-13.1 54.5 23.5 10.594 0.004 0.14 0.03 4125 Lew Allen (H) 11/11-17 247 15.0-12.9 61.4 19.0 4.628 0.002 0.20 0.03 4142 Dersu-Uzala (H) 11/24-12/10 479 17.6-13.7 81.5 13.5 71.2 0.5 0.22 0.03 4690 Strasbourg (H) 09/30-10/28 578 24.6-20.2 31.8 26.4 109.0 1.0 0.80 0.03 4860 Gubbio 10/29-11/09 381 11.2-15.0 20.0 14.2 19.36 0.01 0.85 0.02 6794 Masuisakura 12/22 147 13.2 61.8 9.6 4.58 0.01 0.62 0.02 10171 1995 EE8 12/12-15 173 10.2-10.6 74.1 19.9 8.245 0.005 0.33 0.03 13025 Zurich 10/27-11/11 228 13.4-17.9 23.4 23.6 18.53 0.02 0.24 0.02 15786 1993 RS (H) 10/24-31 251 16.0-18.3 24.0 21.5 13.62 0.01 0.13 0.02 17681 Tweedledum (H) 11/23-12/11 395 4.3,2.0,10.6 64.5 -1.3 75.2 0.5 0.90 0.02 24827 1995 RA 11/18-26 259 20.7-21.0 47.6 31.6 11.653 0.004 0.44 0.02 30019 2000 DD (H) 10/17-23 233 8.5,8.0,8.1 29.5 10.9 6.242 0.005 0.07 0.02 31180 1997 YX3 11/18-26 232 27.5-25.4 68.1 36.1 15.6 0.1 0.25 0.03 31354 1998 TR3 (H) 10/17-29 359 3.7,1.5,4.7 28.6 -2.0 35.39 0.03 0.18 0.02 32814 1990 XZ (H) 11/11-17 222 4.2,0.9,1.1 55.0 0.6 2.8509 0.0005 0.10 0.02 34817 2001 SE116 (H) 12/11-12 188 11.2-10.8 84.0 14.5 6.375 0.003 0.75 0.02 2006 WH1 11/27-28 107 1.8-2.9 63.4 -0.5 7.30 0.02 0.20 0.03 name of an asteroid in the table if it is a member of the Hungaria 17681 Tweedledum. The period is supported by a very good fit to group or family. a half-period monomodal curve at 37.4 hr.

143 Adria. The lightcurve is unusual in that it is quadrimodal. (34817) 2001 SE116. This was follow-up on work previously Lagerkvist (1992) previously reported a period of 11.0 hr. done by the author (Warner 2004).

469 Argentina. Previous reported periods were 3.0 hr (Wang Acknowledgements 2003), 12.3 hr (Szekely 2005), and 13.122 (Wang 2005). The 2005 paper by Wang presented the possibility of non-principal axis Funding for observations at the Palmer Divide Observatory is rotation (NPA or "tumbling"). However, analysis at PDO and by provided by NASA grant NNG06GI32G and by National Science Petr Pravec at Ondrejov Observatory (private communications) Foundation grant AST-0607505. showed no significant evidence of such and that the 17.573 hr period with quadrimodal curve presented here is the most likely References correct solution. Hainaut-Rouelle, M.-C., Hainaut, O.R., Detal, A. (1995). Astron. 595 Polyxena. Previously reported periods were 11.806 hr Astrophys. Suppl. Ser. 112, 125-142. (Hainaut-Rouelle 1995) and Pirronen (1998). The data could be fit to the Hainaut-Rouelle period, but only with a monomodal curve. Harris, A.W., Young, J.W., Bowell, E., Martin, L.J., Millis, R.L., Looking at the plots and observing dates in the H-R paper, it Poutanen, M., Scaltriti, F., Zappala, V., Schober, H.J., Debehogne, appeared that the timing and length of the runs might have allowed H., and Zeigler, K.W. (1989). “Photoelectric Observations of for an alias period to be found. Asteroids 3, 24, 60, 261, and 863.” Icarus 77, 171-186

4142 Dersu-Uzala. A half-period monomodal solution moderately Lagerkvist, C.-I., Magnusson, P., Debehogne, H., Hoffmann, M., supports the 71.2 hr bimodal period. Erikson, A., De Campos, A., Cutispoto, G. (1992), Astron. Astrophys. Suppl. Ser. 95, 461-470. 4690 Strasbourg. The coverage is incomplete but no other solution from 10-200 hr provided a fit near a bimodal curve. Supporting Piironen, J., Lagerkvist, C.-I., Erikson, A., Oja, T., Magnusson, P., the 109 hr period was that fact that a fairly reasonable fit for a Festin, L., Nathues, A., Gaul, M., Velichko, F. (1998). Astron. half-period (monomodal curve) was found near 54.4 hr. Astrophys. Suppl. Ser. 128, 525-540.

6794 Masuisakura. The single night run covered more than 150% Szekely, P., Kiss, L.L., Szabo, Gy.M., Sarneczky, K., Csak, B., of the adopted cycle. The asteroid's size (~35 km) made it unlikely Varadi, M., Meszaros, Sz. (2005). Planet. Space Sci. 53, 925-936. binary candidate and so it was closed after the one session.

Minor Planet Bulletin 34 (2007) 34

Wang, X.-B. (2003). “Abstracts of Photometry and Polarimetry of Asteroids: Impact on Collaboration”, Kharkiv, 32.

Wang, X.-B., Zhang, X.-L., Sheng-Hong, G. (2005). Earth, Moon, and Planets, 97, 3-4, pp. 233-243.

Warner, B.D. (2004). Minor Planet Bul. 31, 19-22.

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Minor Planet Bulletin 34 (2007) 37

ROTATION PERIOD OF ASTEROID 340 EDUARDA AND (Dunham 2005). The initial idea was to observe the asteroid as REFINED PERIOD FOR ASTEROID 71 NIOBE much as possible during its 2006 apparition to look for evidence of the possible satellite and to refine the period and lightcurve of Pedro V. Sada the asteroid. Usable data were collected on 2006 January 6, 7, 30, Departamento de Física y Matemáticas 31; February 2, 3, 6, 26; March 2, 3, 26; and April 4 and 5. All Universidad de Monterrey dates are UT. In total, 1785 images were obtained and processed. Av. I. Morones Prieto 4500 Pte. Of these, 1760 were used in the final analysis. All images were Garza García, N. L., 66238 obtained through a standard Johnson R filter and dark current and MÉXICO flat field corrections were applied. The same nearby LONEOS star [email protected] field (Skiff 2003) with photometric standard stars was observed on most nights to calibrate the magnitudes of the comparison stars. Brian D. Warner Palmer Divide Observatory Asteroid 340 Eduarda was selected because it had only one Colorado Springs, CO 80908 reported rotational period determination listed in the literature (Lagerkvist 1978). At the Universidad de Monterrey Observatory (Received: 3 January) a total of 240 usable images were obtained through a standard Johnson V filter on the nights of 2006 November 19, 22 and 26. Dark current and flat field corrections were also applied, and a CCD photometry of asteroids 71 Niobe and 340 Eduarda nearby LONEOS star field (Skiff 2003) with photometric standard were obtained at the Universidad de Monterrey stars was also observed to calibrate the magnitudes of the field Observatory during 2006. Eduarda was also observed at comparison stars. Observations were also independently obtained the Palmer Divide Observatory during December 2006. at the Palmer Divide Observatory on December 1, 4, 5, and 8. A A synodic rotation period of 8.0062 ± 0.0004 hours and total of 146 usable images were obtained here through a Johnson an amplitude of 0.26 ± 0.02 magnitudes was obtained R filter, with standard image processing techniques performed. for 340 Eduarda from seven nights of observations at both observatories. A refined rotation period for 71 Times were corrected for light travel time from the asteroid to the Niobe is presented from combining 13 nights of Earth and were taken to be at the mid-times of the image observations between January and April 2006 from the exposures. Relative magnitudes from night to night were uncertain Universidad de Monterrey Observatory with previously as different filters and comparison star sets were used. This was published data. The resulting synodic period is 35.81 ± dealt with by using arbitrary additive constants to bring all the data 0.01 hours from a total of 25 nights of observations. into the best agreement possible. These magnitude shifts also took into account intrinsic magnitude variation of the asteroids due to The observations of 71 Niobe and 340 Eduarda from the their change of distance with respect to the Earth, and to phase Universidad de Monterrey Observatory (MPC 720) reported here angle variations. were made with a 36-cm Schmidt-Cassegrain telescope working at f/6.3. The CCD used to gather the data was an SBIG ST-9E with The Universidad de Monterrey observations were initially the chip temperature set between –25o C and –10o C, depending on analyzed independently. The best-fit rotational periods for the ambient conditions. Exposure times varied between 90-120s for asteroids were obtained by computing the power spectrum of the Niobe and 180-240s for Eduarda. The Palmer Divide Observatory time series of data (Scargle 1982; Horne and Baliunas 1986). For (MPC 716) 340 Eduarda observations were obtained with a 50-cm 71 Niobe the preliminary synodic rotational period was 35.84 ± Ritchey-Chretien telescope (f/8.1) and a FLI IMG-1001E CCD 0.01 hours and 8.02 ± 0.01 hours for 340 Eduarda. The resulting operated at –20o C or –10o C, with exposure times of 240s. lightcurve for Niobe was incomplete although the asteroid was observed for more than 67 hours. Also, periods of 14.36 and 20.51 Asteroid 71 Niobe was selected for observation by the first author hours, but with lower power, fit the data with slightly different based on reports of the possible existence of a satellite as magnitude shifts. The fact that the lightcurve showed gaps after so evidenced in two stellar occultations by the asteroid observed on many observations was unfortunate. In particular, 7 of the 13 2004 November 2 in Japan and 2005 February 10 in the USA nights covered the same portion of the lightcurve. The rotation Minor Planet Bulletin 34 (2007) 38 period for 340 Eduarda of nearly exactly 8 hours was also suspect Laguerkvist, C.-I. (1978). “Photographic Photometry of 110 Main- since it was an exact multiple of a day and could have been the Belt Asteroids.” Astron. Astrophys. Sup. 31, 361-381. result of aliasing. Scargle, J. D. (1982). “Studies in Astronomical Time Series At that point the Minor Planet Bulletin published an article on Analysis. II - Statistical Aspects of Spectral Analysis of Unevenly observations made in February 2006 of 71 Niobe (Warner et al. Spaced Data.” Astrophys. J. 263, 835-853. 2006) in which a collaboration of observers had obtained a nearly complete lightcurve in support of radar observations. They found a Skiff, B. (2003). “LONEOS Photometric Calibration Star List.” period of 35.6 ± 0.1 hours and an amplitude of 0.22 ± 0.02 Posted on the WWW: ftp://ftp.lowell.edu/pub/bas/starcats/ magnitudes. The main author was contacted and both sets of data loneos.phot (2003 July 15 update). were then combined in an effort to refine the rotation period and complete the lightcurve. The longer time span of the observations Warner, B. D., Shepard, M. K., Harris, A. W., Crawford, G., and (three months) yielded an improved synodic rotation period of Husárik, M. (2006). “Analysis of the Lightcurve of 71 Niobe.” 35.81 ± 0.01 hours. This result was longer by over two sigma of Minor Planet Bulletin 33, 102. the previously reported uncertainty and also improved the uncertainty by an order of magnitude. The lightcurve remained Warner, B. D. (2006). MPO Software. Bdw Publishing, Colorado nearly the same shape with a few small gaps covered (Figure 1). Springs, CO. Available at: http://www.minorplanetobserver.com/

This contact was also used to collaborate on the lightcurve for 340 Eduarda. Combining both sets of observations confirmed the nearly 8-hour rotation period for the asteroid. A re-reduction of the Universidad de Monterrey Observatory data, this time using MPO Canopus (Warner 2006), yielded a better correlation between both data sets and resulted in a refined period of 8.0062 ± 0.0004 hours and amplitude of 0.26 ± 0.02 magnitudes (Figure 2).

In both figures the time scale is given in rotational phase with the zero corresponding to the epoch, in Julian Day, as indicated.

Previous observations as well as reported rotation periods and lightcurves for 71 Niobe have already been briefly covered by Warner et al. (2006). The present work merely refines the rotation period presented there and evidences the advantages of observing the asteroid for prolonged periods of time. On a side note, no evidence was found in the photometry of small brightness variations due to the suspected presence of a satellite of the asteroid. These were estimated to be no larger than 10-15% from the estimated size of the satellite as measured in the occultations (Dunham, 2005). Either the orbit of the satellite was not favorable Figure 1: Composite lightcurve of asteroid 71 Niobe derived from for eclipses and transits during the observing period, the asteroid 25 nights of observations and a 35.81-hour rotation period. has a smaller satellite than previously suspected, or there is no satellite present. At any rate, radar observations and/or further study of the lightcurve of this asteroid are necessary to resolve the issue of the presence of a satellite around 71 Niobe. The rotation period and shape of the lightcurve, however, are well determined from the data presented here.

The only previous reported rotation period for 340 Eduarda is Lagerkvist (1978), in which a period of 7.68 hours and an amplitude of 0.17 magnitudes from two nights of photographic observations in 1974. The results presented here improve the previously reported period and completely cover the lightcurve of the asteroid.

References

Dunham, D. (2005). “Feb. 10th occultation shows (71) Niobe probably has a large satellite.” Posted on the WWW: http://iota.jhuapl.edu/mp071.htm (2005 February 24 update).

Horne, J. H. and Baliunas, S. L. (1986). “A Prescription for Period Figure 2: Composite lightcurve of asteroid 340 Eduarda derived Analysis of Unevenly Sampled Times Series.” Astrophys. J. 302, from 7 nights of observations and an 8.0062-hour rotation period. 757-763.

Minor Planet Bulletin 34 (2007) 39

ROTATION PERIOD AND AMPLITUDE CHANGE OF Observer Telescope Imaging Details Sessions MINOR PLANET 3868 MENDOZA Oey 0.35m SCT SBIG ST9XE: 7,8,21,23,24,25, Julian Oey f/11 Bin 1x1, unfilt. 27 - 50 Leura Observatory 300 sec integ. 94 Rawson Parade, Leura NSW 2780, Australia 1.07”/pixel. [email protected] Masi et al. 0.80m RC SBIG STL1001E: 11,12,15,16 f/8 Unfiltered, 90sec G. Masi, F. Mallia and U. Tagliaferri Higgins 0.35m SCT SBIG ST8E: 1 - 6, 26 Campo Catino Astronomical Observatory f/4 Bin 1x1, unfilt. 03016 Guarcino – Italy 240 sec integ. Durkee 0.35m SCT SBIG ST10XE: 17,18,19,20,22, David Higgins f/8.6 Bin 3x3, 13,14 Hunters Hill Observatory, 1.4”/pixel. 7 Mawalan Street, Ngunnawal ACT 2913, Australia Miles 0.28m SCT Starlight SXV-H9: 9,10 f/10 Bin 2x2, unfilt. Russell I. Durkee 0.975"/pixel, Shed of Science Observatory 240-300 sec. 5213 Washburn Ave S., Minneapolis, MN 55410, USA Table I. Observers detail with corresponding instruments used.

Richard Miles of Fig. 5 lightcurve due to excessive back ground stars Golden Hill Observatory contamination rendering the curves unusable. The attenuations Grange Cottage, Stourton Caundle, observed by Oey in sessions 8 and 35 and by Durkee in session 22 Dorset DT10 2JP, United Kingdom have been carefully analyzed for possible observational errors mentioned above. (Received: 4 January) A summary of all observers is provided in Table I. The details are self explanatory. The mid-values in each captions of Fig. 2 to Fig. Cumulative data obtained for asteroid 3868 Mendoza 7 correlate to the mid-date of the range of dates shown in the from different observatories over an interval of nearly 3 labels. The total combined lightcurve has been split into 6 months yields a synodic period of 2.77103 + 0.00003 hr individual curves, demonstrating the well-known amplitude-phase and amplitude ranging from 0.07 + 0.05 mag to 0.20 + effect. All data points were accurate to <0.03 mag. A total of 0.05 mag. about 2400 data points was used to determine a synodic period of 2.77103 + 0.00003 hr with amplitude ranging from 0.07 + 0.05 mag to 0.20 + 0.05 mag. 3868 Mendoza was selected for lightcurve studies from a list of targets provided by Pravec (2006) for Photometric Survey of Acknowledgement Asynchronous Binary Asteroids (PSABA). All lightcurve data once obtained and reduced by observers were sent to Pravec for We would like to thank Dr. Petr Pravec of the Astronomical further analysis for signs of binarity. This target was started by Institute, Czech Republic, for his encouragement and support to Higgins. Soon after, Durkee, Masi et al., Miles and Oey joined in the amateur astronomical community through his PSABA project the search during July and August after an initial lightcurve and to Brian Warner for his tireless work in improving the deviation indicated the possibility of the object being binary. Canopus program and great support for its users. However during that time 3868 Mendoza had moved further south, making it favourable only to observers in the southern References hemisphere. Consequently most observations in August and September were done from Leura Observatory and linked nights Pravec, P. (2006). Photometric Survey of Asynchronous Binary with northern hemisphere observers were therefore unobtainable. Asteroids. http://www.asu.cas.cz/~asteroid/binastphotsurvey.htm. While both Higgins and Oey were working on this target in the beginning, it was decided that only Oey was to continue on with this target due to the closeness of their geographical locations. Leura Observatory setups were also more suited to pursue objects as faint as 3868 Mendoza during the apparition.

The quality of the data was moderate at best due to observational difficulty. The trajectory of the asteroid brought it close to the Milky Way star field making accurate observation rather challenging. Most of the data fit well into the predicted lightcurve. When deviations from this trend occur, the data are checked for observational problems such as faint star encroaching within the measuring aperture. For the data obtained from Leura Observatory, Canopus V9.2.0.0 Star-B-Gone feature has been used with care to eliminate most of these faint field stars. The result of this reduction may completely neutralize the value assuming that there are no artifacts introduced especially when it involves low amplitude lightcurves. Sessions 34 has been left out Fig. 1. Composite lightcurve for 3868 Mendoza.

Minor Planet Bulletin 34 (2007) 40

Fig. 2. Mid-value PA 9.9, LPAB 299.0, BPAB 9.5 Fig. 5. Mid-value PA 10.0, LPAB 300.3, BPAB 8.3

Fig. 3. Mid-value PA 6.0, LPAB 299.5, BPAB 9.2 Fig. 6. Mid-value PA 15.9, LPAB 301.4, BPAB 7.5

Fig. 4. Mid-value PA 6.0, LPAB 299.8, BPAB 8.9 Fig. 7. Mid-value PA 24.0, LPAB 305.5, BPAB 5.7

Minor Planet Bulletin 34 (2007) 41

THE LIGHTCURVE OF ASTEROID 7262 SOFUE THE ROTATION PERIOD OF 2183 NEUFANG

Russell I. Durkee Colin Bembrick Shed of Science Observatory Mt Tarana Observatory 5213 Washburn Ave S. Minneapolis, MN 55410 USA PO Box 1537, Bathurst, NSW 2795, Australia [email protected] [email protected]

Donald P. Pray Greg Bolt Carbuncle Hill Observatory 295 Camberwarra Drive, Craigie, WA 6025, Australia Coventry, RI 02816 Bill Allen Petr Pravec Vintage Lane Observatory Ondrejov Observatory 83 Vintage Lane, RD3, Blenheim, New Zealand 25165 Ondrejov, Czech Republic (Received: 10 January) (Received: 8 January Revised: 13 January)

Minor planet 2183 Neufang was observed over 8 nights Asteroid 7262 Sofue was observed during June 7-23, in 2006. The synodic period was determined as 3.8662 ± 2006. A synodic period of 8.2223 ± 0.0003 hr with a 0.0008 hr. The peak to peak amplitude was 0.3 mag, mean amplitude of 0.46 ± 0.02 mag was derived. implying an axial ratio (a/b) of 1.32

Observations of 7262 Sofue were carried out over five nights in Minor planet 2183 Neufang (1959 OB) was discovered by C. June of 2006. Five nights of observations were completed at the Hoffmeister at Bloemfontein in July 1959. It was named after a Shed of Science and one night at Carbuncle Hill Observatory. village near Sonneberg Observatory. This is an outer main-belt Both observatories observed the object the night of June 22, asteroid with a diameter of 37.5 km and an albedo of 0.035 covering about 0.8 of the derived period. All CCD exposures (GUIDE ver 8). The latest list of rotational parameters (Harris & were unfiltered. Our derived period is unique and rated as U=3. Warner, 2006) has no quoted period. However, Schober et al (see Harris 2006 for explanation of U). Asteroid 7262 Sofue was (1994) suggest “a short rotation period” on the basis of a brief initially selected for observation as part of the Photometric Survey partial lightcurve with approximately 0.1 mag variation. for Asynchronous Binary Asteroids led by Petr Pravec of the Ondrejov Observatory, Czech Republic (2005). Initially these data The observations of Neufang in 2006 were conducted from three were sent to Pravec as part of the survey. Analysis was performed sites – one in New Zealand and two in Australia. The locations of using MPO Canopus by Brian Warner. these sites are listed in Bembrick et al (2004). All observations were made using unfiltered differential photometry and all data References were light-time corrected. The aspect data (Table I) also shows the percentage of the lightcurve observed each night. PAB is the Harris, A.W. and Warner, B.D., 2006. “Minor Planet Lightcurve Phase Angle Bisector. Period analysis was carried out using the Parameters”. Updated March 14, 2006. “Peranso” software (Vanmunster, 2006). Various routines http://cfa-www.harvard.edu/iau/lists/LightcurveDat.html available in Peranso were used (including the “FALC” routine based on Harris et al 1989) and these gave near identical results, Pravec, P. (2005). “Prepublished Periods of Asteroids”. with a single strong peak in the power spectrum. The final analysis http://www.asu.cas.cz/~ppravec/newres.htm determined a period of 3.8662 +/- 0.0008 hours which was used to compile the composite lightcurve with the arbitrary zero phase maximum at JD 2454010.0 (see Figure 1). The peak to peak variation implies an axial ratio (a/b) of 1.32. Full phase coverage was achieved and this is considered a secure result.

Minor Planet Bulletin 34 (2007) 42

References Schober, H.J., Erikson, A., Hahn, G., Lagerkvist, C.-I., Albrecht, R., Ornig, W., Schroll, A., Stadler, M. (1994). Astron. Astrophys. Bembrick, C.S., Richards, T., Bolt, G., Pereghy, B., Higgins, D. Suppl. Ser. 105, 281-300. and Allen, W.H. (2004). “172 Baucis – A Slow Rotator”. Minor Planet Bulletin, 31, 51-52. Vanmunster, T., 2006. Peranso ver 2.0. http://www.peranso.com

GUIDE version 8 (2002). http://www.projectpluto.com UT Date PAB PAB Phase %Phase Harris, A.W. and Warner, B.D. (2006). “Minor Planet Lightcurve Long Lat Angle Coverage Parameters”. Updated March 14, 2006. 2006 Oct 01 19.8 -24.4 15.9 85 http://cfa-www.harvard.edu/iau/lists/LightcurveDat.html 2006 Oct 03 20.0 -24.3 15.5 116 2006 Oct 09 20.4 -24.0 14.4 138 Harris, A.W., Young, J.W., Bowell, E., Martin, L. J., Millis, R. L., 2006 Oct 13 20.7 -23.7 13.9 135 2006 Oct 14 20.8 -23.6 13.8 118 Poutanen, M., Scaltriti, F., Zappala, V., Schober, H. J.,Debehogne, 2006 Oct 15 20.8 -23.5 13.8 70 H, and Zeigler, K. (1989). “Photoelectric Observations of 2006 Oct 18 21.0 -23.3 13.7 80 Asteroids 3, 24, 60, 261, and 863.” Icarus 77, 171-186. 2006 Oct 25 21.5 -22.5 14.0 125 Table I. Aspect data for Neufang in 2006.

LIGHTCURVE OF MINOR PLANET 5740 TOUTOUMI checking references (Minor Planet Bulletin) there are no previously reported data on period or lightcurve characteristics. Gary A. Vander Haagen Stonegate Observatory, 825 Stonegate Road Acknowledgments Ann Arbor, MI 48103 [email protected] The author appreciates the help from Brian Warner on Canopus period analysis and his continued encouragement on asteroid (Received: 10 January Revised: 14 January) photometric studies.

References Lightcurves of 5740 Toutoumi spanning 29 days from December 10, 2006 through January 7, 2007 with 890 Warner, B.D., 2006, MPO Software, Canopus version 9.2.0.0, data points produced a rotation period of 11.68 ± 0.10 hr Bdw Publishing, http://minorplanetobserver.com/ at an amplitude of 0.33 ±0.03 mag. Astrometric data were also submitted to the Minor Planet Center for the Vannmunster, T., 2006. Peranso Period Analysis Software, same time period. Peranso version 2.10, CBABelgium, http://users.skynet.be/ fa079980/peranso/index.htm

Astrometric and photometric data for 5740 Toutoumi were Harris, A.W., Young, J.W., Bowell, E., Martin, L.J., Millis, R.L., collected using a 36 cm Celestron C-14, a SBIG ST-10XME Poutanen, M., Scaltriti, F., Zappala, V., Schober, H.J., Debehogne, camera, and clear filter at Stonegate Observatory. The pixels were H., and Zeigler, K.W., (1989). “Photoelectric Observations of binned 2X2 with a resultant image scale of 1.4 arc-seconds per Asteroids 3, 24, 60, 261, and 863.” Icarus 77, 171-186. pixel. The camera temperature was held at –15C for all measurements. All images were 60 seconds and unguided. Potential Lightcurve Targets 2006 October-December, CALL web site. http://www.minorplanetobserver.com/astlc/targets Data were collected on every available clear night from December 10, 2006, through January 7, 2007, resulting in six data sets. During this time, 5740 Toutoumi started at magnitude 15.4 moving at 0.53 arc-seconds/minute and ended at magnitude 16.1 moving at 0.20 arc-seconds/minute. Clouds and numerous weather interruptions occurred during the data collection period. Typical FWHM seeing conditions were poor, ranging from 2.8 to more than 5.0 arc-seconds. Of the six data runs, four were between 2 and 3.6 hours while the remaining two went more than 6 hours. In all, 890 data points were collected. The photometric data were obtained using MPO Canopus (Warner 2006). A period of 11.68 ±0.10 hours was determined.

The data were also analyzed using Peranso version 2.10 (Vannmunster 2006) using the FALC (Harris 1989) method. Here the highest probability solution was again confirmed as 11.68 hours. Another probable solution at 5.57 hours was also investigated. This solution was discarded after further data and verification of the large amplitude portion of the lightcurve 5740 Toutoumi photometric data phased to a period of 11.68 between phase 0.75 and 1.0. The photometric noise level between hours using a zero point of JD = 2454079.756. 0.02 to 0.05 magnitude prohibited a higher accuracy solution. In Minor Planet Bulletin 34 (2007) 43

LIGHTCURVE ANALYSIS OF MINOR PLANETS 2544 GUBAREV AND 2599 VESELI

Greg Bolt 295 Camberwarra Drive, Craigie, WA 6025, Australia [email protected]

Colin Bembrick Mt Tarana Observatory PO Box 1537, Bathurst, NSW 2795, Australia

(Received: 12 January)

Minor planet 2599 Veseli was observed over four nights in July 2004, and minor planet 2544 Gubarev was observed over eight nights in April 2005. The synodic rotation period for 2544 Gubarev was found to be 4.750 Figure 1. The lightcurve of 2544 Gubarev phased to 4.750hr. ± 0.001 hr with an amplitude of 0.42 mag. For 2599 Veseli, the results were less secure and found to fit two possible synodic periods, 13.25 ± 0.05 hr and 18.54 ± 0.05 hr, with an amplitude of 0.33 mag.

Minor planet 2599 Veseli was observed over four nights in July 2004 from Craigie, Western Australia. Minor planet 2544 Gubarev was observed over eight nights in April 2005 from Craigie and Mt Tarana Observatory in NSW, Australia. The locations of both sites are listed in Bembrick et al. (2004). All observations were carried out using unfiltered photometry and the data were then light-time corrected. Analysis was performed using “Peranso” (Vanmunster 2006) using primarily the “FALC” (Harris et el 1989) and “ANOVA” methods. The latest list of rotational parameters (Harris & Warner 2006) lists no period for either minor planet.

2544 Gubarev: Analysis of the data for this minor planet resulted Figure 2. The lightcurve of 2599 Veseli phased to 13.25hr. in a single strong peak in the power spectrum. Full phase coverage was achieved making this a secure result. Figure 1 shows the data phased to the resulting period of 4.750 ± 0.001 hr.

2599 Veseli: It is clear the data obtained do not cover a full phase and, after careful analysis, two possible synodic periods were found, both of which are bimodal. Figure 2 shows the data phased to a period of 13.25 ± 0.05 hr and Figure 3 shows the data phased to a period of 18.54 ± 0.05 hr. Based on phase coverage and overlap, the former is considered to be the more realistic period.

References

Bembrick, C.S., Richards, T., Bolt, G., Pereghy, B., Higgins, D. and Allen, W.H. (2004). “172 Baucis – A Slow Rotator”. Minor Planet Bulletin, 31, 51-52.

Harris, A.W. and Warner, B.D. (2006). “Minor Planet Lightcurve Parameters”. Updated March 14, 2006. Figure 3. The lightcurve of 2599 Veseli phased to 18.54hr. http://cfa-www.harvard.edu/iau/lists/LightcurveDat.html

Harris, A.W., Young, J.W., Bowell, E., Martin, L. J., Millis, R. L., Poutanen, M., Scaltriti, F., Zappala, V., Schober, H. J.,Debehogne, H, and Zeigler, K., (1989). “Photoelectric Observations of Asteroids 3, 24, 60, 261, and 863”. Icarus 77, 171-186.

Vanmunster, T. (2006). Peranso ver 2.11. http://www.peranso.com

Minor Planet Bulletin 34 (2007) 44

LIGHTCURVE ANALYSIS OF ASTEROIDS f/5.5 reflector with an AP8p CCD camera. Image dimensions were 2006 BQ6, 2942, 2943, 3402, 3533, 6497, 6815, 7033, 25 arcmin squared (1.5 arcsec per pixel). All images were taken 12336, AND 14211 through the “clear” filter. Ondřejov Observatory used a 0.65m, f/3.6, reflector with an Apogee AP7p CCD at the prime focus, and Donald P. Pray an R filter designed to closely match the Cousins system. The Carbuncle Hill Observatory image dimensions were 18x18 arcminutes. Skalnaté Pleso 272 Nicholas Rd., Greene, RI, 02827, USA Observatory used a 0.61-m f/4.2 Newtonian reflector and a SBIG [email protected] ST-8XME CCD camera. Frames were binned 2x2 (1.4 arcsec per pixel). Differential photometry was performed through a Johnson- Peter Kušnirák Cousins R filter. Ondřejov Observatory, Astronomical Institute Academy of Sciences of the Czech Republic All but one of the targets were selected from a list provided by Ondřejov, Czech Republic Pravec (2006) as part of his “Photometric Survey of Asynchronous Binary Asteroids” study. The asteroid 2006 BQ6 was a radar Adrián Galád, Jozef Világi, Leoš Kornoš and Štefan Gajdoš target observed at Goldstone by Lance Benner, et al, and the Modra Observatory photometric observations presented here were made in support of Department of Astronomy, Physics of the Earth, and Meteorology that effort. At CHO, image calibration via dark frames, bias Bratislava, Slovakia frames and flat field frames was performed using “MaxIm DL”. Lightcurve construction and analysis was accomplished using Michal Pikler, Gabriel Červák, and Marek Husárik “Canopus” developed by Brian Warner. Differential photometry Skalnaté Pleso Observatory was used in all cases, and all measurements were corrected for AI SAS, Tatranská Lomnica, Slovakia light travel time. [email protected] Results are shown in Table I. Column headings are self- Julian Oey explanatory. Plots of the lightcurves are also presented. Leura Observatory Leura, NSW 2780, Australia 2942 Cordie. This appears to be a tumbling asteroid, that is, one that rotates about more than one axis. This explains the Walt Cooney, John Gross, and Dirk Terrell “disrupted” lightcurve. The ~81 hour rotation is probably due Sonoita Research Observatory mostly to the primary rotation axis. This period is subject to a high Sonoita, AZ, USA degree of interpretation and may be significantly different. The Robert D. Stephens data were mutually linked to an internal, instrumental system. Goat Mt. Astronomical Research Station Rancho Cucamonga, CA 6815 Mutchler. Three complete and/or partial attenuations were seen for 6815 Mutchler, and it was confirmed to be a binary David Higgins asteroid (Pravec, 2006). Because of various circumstances, Hunters Hill Observatory insufficient data was collected to determine an orbital period. Ngunnawal, ACT, Australia (7033) 1994 WN2. This asteroid showed one, partial attenuation. (Received: 12 January Revised: 16 January) However, since this was never confirmed by other data, nothing can be concluded from it.

Lightcurve periods and amplitudes are reported for ten None of the asteroids presented here had had their periods asteroids observed at Carbuncle Hill Observatory and determined before. other sites during April 2006-December 2006. Acknowledgements

Of the asteroids reported here, three were observed exclusively at Research at Modra was supported by VEGA, the Slovak Grant Carbuncle Hill Observatory (CHO), while the remaining seven Agency for Science Grant 1/3074/06. The work at Ondřejov was involved collaborations with fourteen observers from seven other supported by the Grant Agency of the Czech Republic, Grant observatories. Targets in Table I are noted to show contributors 205/05/0604. Research at Skalnaté Pleso Observatory was and their affiliation. Observations at CHO were made with a supported by grant 4012 from VEGA, the Slovak Grant Agency 0.51m f/4 reflector with a SBIG ST-10XME CCD camera at the for Science. Thanks are given to Brian Warner for his continued prime focus. This system produced an image dimension of 28x17 development and improvement of the program, “Canopus”, and to arcmin (2.1 arcsec per pixel, binned 3x3). All observations were Petr Pravec for his general help and encouragement in the field of taken through the “clear” filter. Goat Mountain Astronomical asteroid research. Research Station obtained images using a 0.35m, f/11SCT, and a SBIG STL1001E CCD. The field of view was 21x21 arcmin (1.23 References arcsec/pixel binned 1x1). All images were taken through the “clear” filter. Hunters Hill Observatory used a 0.35m SCT and Pravec, P. (2006). Photometric Survey of Asynchronous Binary SBIG ST-8E CCD. Images were taken using the “clear” filter and Asteroids, http://www.asu.cas.cz/~asteroid/binastphotsurvey.htm. guided exposures of 240 seconds at a resolution of 1.31 arcsec/pixel. Leura Observatory used a 0.35m SCT at f/11 and a SBIG ST9XE CCD at the prime focus. The camera was operated at 1x1 data binning resulting in an image dimension of 9.1 x 9.1 arcmin (1.07 arcsec per pixel). Modra Observatory used a 0.6m, Minor Planet Bulletin 34 (2007) 45

Minor Planet Bulletin 34 (2007) 46

Date Range # Name Images Per (h) P.E. Amp Phase LPAB BPAB (2006) 2006 BQ (6) 08/05-06 110 4.416 0.002 1.6 64.8-60.9 342.8 18.7 2942 Cordie (6) 04/16-05/24 258 ~81 ND ~1 10.7-24.6 190.9 9.5 2943 Heinrich (5,6,7) 08/17-31 309 8.7925 0.0005 0.20 22.5-18.0 3.1 10.7 3402 Wisdom (5,6,10) 09/26-10/22 203 4.9949 0.0001 0.75 1.6-15.0 0.8 3.7 3533 Toyota (3,5,6) 11/25-29 366 2.9807 0.0003 0.18 7.7-5.7 72.6 -5.7 6497 Yamasaki (6) 09/28-11/11 198 9.879 0.001 0.56 10.4-16.9 17.9 4.9 6815 Mutchler (1,4,5,6,9) 10/14-11/09 710 2.4384 0.0001 0.09 5.6-15.2 28.6 1.6 7033 1994 WN2 (1,6,8,11) 05/05-06/04 675 2.8158 0.0001 0.09 7.0-18.5 216.7 9.5 12336 1992 WO3 (2,6) 11/25-12/11 167 2.9527 0.0001 0.20 12.2-15.4 68.8 -14.8 14211 1999 NT1 (5,6) 7/15-25 373 3.5850 0.0002 0.14 22.9-20.7 320.6 15.8

(1) Galád (Modra); (2) Cooney, Gross, Terrell (Sonoita); (3) Husárik, Červák, Pikler (Skalnate Pleso); (4) Gajdoš (Modra); (5) Kušnirák (Ondrejov); (6) Pray (Carbuncle Hill); (7) Kornoš and Világi (Modra); (8) Oey (Leura); (9) Stephens (GMARS); (10) Pikler (Skalnate Pleso); (11) Higgins (Hunters Hill) Table I. Summary of results

LIGHTCURVE ANALYSIS OF (34777) 2001 RH

Robert D. Stephens Goat Mountain Astronomical Research Station (GMARS) 11355 Mount Johnson Court, Rancho Cucamonga, CA 91737 [email protected]

Brian D. Warner Palmer Divide Observatory 17995 Bakers Farm Rd., Colorado Springs, CO 80908 [email protected]

(Received: 10 January)

Observations of (34777) 2001 RH were made in late 2006 and early 2007. Analysis yields a lightcurve period Acknowledgements of 7.4947 ± 0.0004 hr and amplitude of 0.40 ± 0.02 mag. Funding for observations at the Palmer Divide Observatory is provided by NASA grant NNG06GI32G and by National Science Stephens selected (34777) 2001 RH at random while observing at Foundation grant AST-0607505. his GMARS observatory on Dec. 31, 2006. He used a 0.35m SCT/RCX with SBIG ST1001 CCD camera operating at –30C. References His data covered a majority of what would be the adopted period, but were split into two "sessions", meaning two sets of comparison Harris, A.W., Young, J.W., Bowell, E., Martin, L.J., Millis, R.L., stars were used for photometry analysis because of the asteroid's Poutanen, M., Scaltriti, F., Zappala, V., Schober, H.J., Debehogne, motion. Since Stephens would not be able to observe the asteroid H., and Zeigler, K.W. (1989). “Photoelectric Observations of again for some time, he passed his observations onto Warner, who Asteroids 3, 24, 60, 261, and 863.” Icarus 77, 171-186. then observed it on two nights, Jan. 9-10, 2007, using a 0.35m SCT and FLI-1001E CCD camera. The table gives the viewing aspects on the three dates of observation. Note that the asteroid reached a minimum phase angle (α) of ~2.8° on Jan. 3, 2007.

Date Phase PABL PABB 2006 Dec 31 4.2 101.1 4.8 2007 Jan 09 5.4 101.4 0.5 2007 Jan 10 6.2 101.4 0.0

Each author measured his images using MPO Canopus, which employs differential aperture photometry to produce the raw data. Period analysis by Warner was done using Canopus, which incorporates the Fourier analysis algorithm (FALC) developed by Harris (1989).

Minor Planet Bulletin 34 (2007) 47

LIGHTCURVE RESULTS FOR 486 CREMONA, 3908 Nyx. Photometry of 3908 Nyx was undertaken at SRO in 855 NEWCOMBIA, 942 ROMILDA, 3908 NYX, support of Arecibo radar observations by Lance Benner and 5139 RUMOI, 5653 CAMARILLO, (102866) 1999 WA5 coworkers. This NEO has been studied previously by Drummond and Wisniewski (1990), Hoffman and Geyer (1990), Wisniewski Walter R. Cooney, Jr. (1992), and Benner et al. (2002). Kaasalainen et al. (2003) noted a 1927 Fairview Dr. rapid change in lightcurve shape. In the 40 days separating the Port Allen, LA 70767 first two sessions and the third session at SRO, the curve changes [email protected] enough that it cannot be phased solely on the basis of the shape of the curve. During that period the phase angle changed from 65.9 to John Gross, Dirk Terrell 33.4 deg. The data presented below are phased with a 4.42601 hr Sonoita Research Observatory period derived by Kassalainen et al. (2003). The 12/13/2004 data Sonoita, Arizona USA are shifted along the magnitude axis to show the change of shape more clearly. These data are not calibrated against each other Vishnu Reddy nightly so it is not possible to know how to shift them Department of Earth System Science & Policy appropriately without the geometric cues of a consistently shaped University of North Dakota lightcurve. Within the precision of these data, the amplitude of the Grand Forks, North Dakota USA November and December sessions remains 0.4 ± 0.05 mag.

Ron Dyvig 5139 Rumoi. A period of 3.257 ± 0.003 hr was derived from two Badlands Observatory nights of photometry at Sonoita Research Observatory. The South Dakota, USA amplitude was 0.4 ± 0.05 mag. No previous period for Rumoi has been published per Harris and Warner (2006). (Received: 12 January) 5653 Camarillo. A period of 4.834 ± 0.005 hr was derived from Differential photometry results for seven asteroids are three nights of photometry at Sonoita Research Observatory and reported here. The synodic period for 486 Cremona was one night from Badlands Observatory. The amplitude was 0.5 ± found to be 61.15 hr with an amplitude of 0.8 mag; 855 0.1 mag. The period derived matches the 4.8341 hr result by Newcombia – 3.003 hr and 0.35 mag; 942 Romilda – Mottola et al. (1995) in January 1993. During that apparition, 6.965 hr and 0.35 mag; 5139 Rumoi – 3.257 hr and 0.4 Mottola et al. (1995) found the amplitude to be 0.85 mag. mag; 5653 Camarillo – 4.834 hr and 0.5 mag; (102866) 1999 WA5 – 3.09 hr and 0.35 mag. 3908 Nyx shows (102866) 1999 WA5. A period of 3.09 ± 0.02 hr was derived from fast changes in lightcurve shape as previously seen by two nights of photometry at Sonoita Research Observatory. The Kaasalainen et al. (2003). amplitude was 0.35 ± 0.1 mag. No previous period for 1999 WA5 has been published per Harris and Warner (2006).

Minor planet lightcurves obtained at Sonoita Research References Observatory, Blackberry Observatory, and in collaboration with Badlands Observatory are reported here. Sonoita Research Benner, L.A. M., Ostro, S.J., Hudson, R.S., Rosema, K.D., Observatory employs a 0.35m f/11 SCT with an SBIG STL-1001E Jurgens, R.F., Yeomans, D.K., Campbell, D.B., Chandler, J.F., CCD camera. Blackberry Observatory houses a 0.3m f/10 SCT Shapiro, I. I. (2002) “Radar Observations of Asteroid 3908 Nyx”, with an Apogee AP-7p CCD camera. Badlands Observatory is Icarus 158, 379-388. equipped with a 0.66m f/4.8 Newtonian with an Apogee AP-8 CCD camera. All times and dates reported are UT. Light-time Drummond, J.D. and Wisniewski, W.Z. (1990). “The Rotational correction has been incorporated. All data reported are unfiltered Poles and Shapes of 1580 Betulia and 3908 (1980PA) from One differential and phased by shifting along the magnitude axis. Apparition”, Icarus 83, 349-359.

486 Cremona. Wisniewksi et al. (1997) observed this asteroid on a Harris, A.W. and Warner, B.D. (2006). “Minor Planet Light Curve single night in 1992 and were unable to derive a period from those Parameters”, on Minor Planet Center web site: http:cfa- data. Palmer Divide Observatory observed Cremona during the www.Harvard.edu/iau/lists/LightcurveDat.html. 2006 apparition over six nights spanning a thirteen-day interval. The period derived was 65.9 hours as published in Warner (2006). Hoffmann, M. and Geyer, E.H. (1990) “Photometric Observations Blackberry Observatory also observed Cremona during the 2006 of Three Near-Earth Asteroids”, Acta Astronomica 40, 389-396. apparition. Over a 60 night interval, the period was refined to 65.15 ± 0.1 hr from fifteen nights of photometry. The amplitude Kaasalainen, M., Pravec, P., Krugly, Y., Sarounova, L., Torppa, J., was 0.8 ± 0.05 mag. Virtanen, J., Kaasalainen, S., Erikson, A., Nathues, A., Durech, J., Wolf, M., Lagerros, J., Lindgren, M., Lagerkvist, C., Koff, R., 855 Newcombia. A period of 3.003 ± 0.007 hr was derived from Davies, J., Mann, R., Kusnirak, P., Gaftonyuk, N., Shevchenko, two nights of photometry at Sonoita Research Observatory (SRO). V., Chiorny, V., Belskaya, I. (2003) “Photometry and Models of The amplitude was 0.35 ± 0.03 mag. No previous period for Eight Near-Earth Asteroids”, Icarus 167, 178-196. Newcombia has been published per Harris and Warner (2006). Mottola, S., De Angelis, G., Di Martino, M., Erikson, A., Hahn, 942 Romilda. A period of 6.965 ± 0.003 hr was derived from G., Neukum, G. (1995). “The Near-earth Objects Follow-up seven nights of photometry at Blackberry Observatory. The Program: First results.” Icarus 117, 62-70. amplitude was 0.35 ± 0.05 mag. No previous period for Romilda has been published per Harris and Warner (2006).

Minor Planet Bulletin 34 (2007) 48

Warner, B. D. (2006) “Asteroid Lightcurve Analysis at the Palmer Divide Observatory – February-March 2006.” The Minor Planet Bulletin 33(4), pp 82-84.

Wisniewski, W.Z. (1992) “The Unusual Lightcurve of 1990 TR” in Asteroids, Comets, Meteors 1991. (A.W. Harris and E. Bowell, eds.) Lunar and Planetary Institute, Houston, pp. 653-656.

Wisniewski, W.Z., Michalowski, T.M., Harris, A.W., McMillan, R. S.: (1997) “Photometric Observations of 125 Asteroids.” Icarus 126, 395-449.

No. Name Phase Period Err Amp. Err 486 Cremona 3.7-18.9 65.15 0.1 0.8 0.05 855 Newcombia 5.5-6.0 3.003 0.007 0.35 0.03 942 Romilda 13.2-3.0 6.965 0.003 0.35 0.05 3908 Nyx 65.9-33.4 0.4 0.05 5139 Rumoi 2.9-3.6 3.257 0.003 0.4 0.05 5653 Camarillo 25-21.5 4.834 0.005 0.5 0.1 102866 1999 WA5 19.3-19.9 3.09 0.02 0.35 0.1

Minor Planet Bulletin 34 (2007) 49

THE LIGHTCURVE OF ASTEROID 1906 NAEF Ryan, W., Ryan E. (2007) , Personal communication. [email protected], [email protected]. Russell I. Durkee Shed of Science Observatory 5213 Washburn Ave S. Minneapolis, MN 55410 USA [email protected]

Petr Pravec Ondrejov Observatory 25165 Ondrejov, Czech Republic

(Received: 5 January Revised: 10 January)

Asteroid 1906 Naef was observed during Sept. 21-Oct. 8, 2005. A synodic period of 11.0090 ± 0.0002 hr with a mean amplitude of 0.92 ± 0.02 mag was derived.

Observations of 1906 Naef were carried out over three nights in late September and early November 2005. All observations were unfiltered. Our derived period is unique and rated as U=3 (see Harris 2006). The minimum covered on Sept. 21 and Oct. 8 shows a small amplitude change of about 0.04 mag., which correlates with decreased solar phase angle. This is consistent with preliminary observations taken at the Vatican Advanced Technology telescope on Sept. 24-27, 2005 by Ryan and Ryan (2007) who found an 11 hour period and a 0.96 mag. amplitude. Asteroid 1906 Naef was initially selected for observation as part of the Photometric Survey for Asynchronous Binary Asteroids led by Petr Pravec of the Ondrejov Observatory, Czech Republic (Pravec 2005). These data were initially sent to Pravec as part of the survey. Analysis was performed using MPO Canopus by Brian Warner.

References

Harris, A.W. and Warner, B.D., 2006. “Minor Planet Lightcurve Parameters”. Updated March 14, 2006. http://cfa-www.harvard.edu/iau/lists/LightcurveDat.html

Pravec, P. (2005). “Prepublished Periods of Asteroids”. http://www.asu.cas.cz/~ppravec/newres.htm

Minor Planet Bulletin 34 (2007) 50

LIGHTCURVE PHOTOMETRY OPPORTUNITIES belt asteroids where the maximum phase angle is about 30°. APRIL – JUNE 2007 However, the extra effort can and will pay off.

Brian D. Warner The fourth list gives a brief ephemeris for planned radar targets. Palmer Divide Observatory/Space Science Institute Supporting optical observations made to determine the 17995 Bakers Farm Rd. lightcurve’s period, amplitude, and shape are needed to Colorado Springs, CO 80908 USA supplement the radar data. Reducing to standard magnitudes is not [email protected] required but high precision work usually is, i.e., on the order of 0.01-0.03mag. A geocentric ephemeris is given for when the Alan W. Harris asteroid is brighter than 16.0 (in most cases). The date range may Space Science Institute not always coincide with the dates of planned radar observations, La Canada, CA 91011-3364 USA which – for Arecibo – are limited to a relatively narrow band of declinations. Petr Pravec Astronomical Institute Those obtaining lightcurves in support of radar observations CZ-25165 Ondrejov, Czech Republic should contact Dr. Benner directly at the email given above. There are two web sites of particular interest for coordinate radar and Mikko Kaasalainen optical observations. Future targets (up to 2010) can be found at Rolf Nevanlinna Institute http://echo.jpl.nasa.gov/~lance/future.radar.nea.periods.html. Past FIN-00014 University of Helsinki, Finland radar targets, for comparison to new data, can be found at http://echo.jpl.nasa.gov/~lance/radar.nea.periods.html. Lance A.M. Benner Jet Propulsion Laboratory Once you have data and have analyzed them, it’s important that Pasadena, CA 91109-8099 USA you publish your results, if not part of a pro-am collaboration, then We present here four lists of “targets of opportunity” for the in the Minor Planet Bulletin. It’s also important to make the data period 2007 April – June. The first list is those asteroids reaching available at least on a personal website or upon request. a favorable apparition during this period, are <15m at brightest, and have either no or poorly constrained lightcurve parameters. By Note that the lightcurve amplitude in the tables could be more, or “favorable” we mean the asteroid is unusually brighter than at less, than what’s given. Use the listing as a guide and double- check your work. Also, if the date is '1 01. ' or '12 31. ', i.e., there other times. In many cases, a favorable apparition may not come again for many years. The goal for these asteroids is to find a well- is no value after the decimal, it means that the asteroid reaches its determined rotation rate, if at all possible. Don’t hesitate to solicit brightest just as the year begins (it gets dimmer all year) or it reaches its brightest at the end of the year (it gets brighter all help from other observers at widely spread longitudes should the year). initial finding for the period indicated that it will be difficult for a single station to find the period. Funding for Warner and Harris in support of this article is The Low Phase Angle list includes asteroids that reach very low provided by NASA grants NNG06GI32G and NNX06AB30G and by National Science Foundation grant AST-0607505. phase angles. Getting accurate, calibrated measurements (usually V band) at or very near the day of opposition can provide Lightcurve Opportunities important information for those studying the “opposition effect”, which is when objects near opposition brighten more than simple Brightest Harris Data geometry would predict. # Name Date Mag Dec U Period Amplitude ------872 Holda (F) 4 04.1 12.8 - 6 2 7.2 0.34 The third list is of those asteroids needing only a small number of 3028 Zhangguoxi (F) 4 04.6 14.5 - 5 2 4.401 0.12 lightcurves to allow Kaasalainen and others to complete a shape 5654 Terni (F) 4 04.7 14.7 - 6 0 model. Some of the asteroids have been on the list for some time, 1274 Delportia (F) 4 05.0 13.6 -12 0 5484 Inoda (F) 4 08.0 14.9 + 5 0 so work on them is strongly encouraged in order to allow models 3497 Innanen (F) 4 09.5 14.8 + 4 0 to be completed. For these objects, we encourage you to do 2856 Roser (F) 4 10.0 14.9 - 8 2+ 13.73 0.49 absolute photometry, meaning that the observations are not 3166 Klondike (F) 4 10.1 14.8 + 0 0 1704 Wachmann (F) 4 11.2 15.0 -10 0 differential but absolute values put onto a standard system, such as 4105 Tsia (F) 4 15.7 14.9 -10 0 Johnson V. If this is not possible or practical, accurate relative 1421 Esperanto (F) 4 17.3 14.1 - 6 0 photometry is also permissible. This is where all differential 2190 Coubertin (F) 4 18.2 14.8 -12 0 values are against a calibrated zero point that is not necessarily on 7836 1993 TG (F) 4 22.6 15.0 - 9 0 13351 Zibeline (F) 4 22.8 14.8 -10 0 a standard system. 18285 1972 GJ (F) 4 27.0 14.9 -14 0 1813 Imhotep (F) 4 27.1 14.4 -14 2 17.978 0.46 When working any asteroid, keep in mind that the best results for 533 Sara (F) 4 28.8 13.5 - 8 2 12.0 0.26 7304 Namiki (F) 4 28.9 13.7 +13 0 shape and spin axis modeling are obtained when lightcurves are 2145 Blaauw (F) 4 30.4 14.9 -30 0 obtained over a range of phase angles, let alone viewing aspects at 4853 Marielukac (F) 5 02.7 15.0 + 0 0 different apparitions. Higher phase angles allow shadowing effects 1465 Autonoma (F) 5 02.8 14.9 - 3 0 5560 Amytis (F) 5 04.6 14.8 -10 0 to influence the lightcurve and help constrain the modeling 5854 1992 UP (F) 5 04.6 14.7 -14 0 solution. If at all possible, try to get lightcurves not only close to 1415 Malautra (F) 5 04.8 14.1 -22 0 opposition when the asteroid is usually near its brightest, but 2425 Shenzhen (F) 5 05.1 14.9 -14 0 before and after, e.g., when the phase angle is 15° or more. This 3656 Hemingway (F) 5 10.5 14.9 -19 0 3406 Omsk (F) 5 11.3 14.3 -27 0 can be difficult because of the geometry involved, especially main 5826 1990 DB (F) 5 16.7 14.8 -15 0 632 Pyrrha (F) 5 17.2 13.7 -23 1 4.6 0.4 Minor Planet Bulletin 34 (2007) 51 Lightcurve Opportunities (continued) Low Phase Angle Opportunities (continued)

Brightest Harris Data # Name Date α V Dec # Name Date Mag Dec U Period Amplitude ------1044 Teutonia 06 07.4 0.98 13.3 -25 1451 Grano (F) 5 17.3 14.3 -10 0 268 Adorea 06 14.0 0.81 12.1 -21 1388 Aphrodite (F) 5 18.0 12.6 -20 2 11.95 0.35 121 Hermione 06 19.5 0.79 12.1 -26 4091 Lowe (F) 5 19.1 14.5 -22 2- 12.57 0.1 182 Elsa 06 23.9 0.31 12.6 -23 3049 Kuzbass (F) 5 20.6 15.0 -18 0 1294 Antwerpia 06 24.1 0.90 14.0 -26 13538 1991 ST (F) 5 23.1 14.9 -16 0 1064 Aethusa 06 27.4 0.84 12.5 -25 3519 Ambiorix (F) 5 23.2 14.3 -21 0 18835 1999 NK56 (F) 5 25.2 14.6 -29 0 913 Otila (F) 5 25.6 13.3 -14 0 Shape/Spin Modeling Opportunities 5305 1978 VS5 (F) 5 26.1 15.0 -20 0 3275 Oberndorfer (F) 5 26.3 14.6 -27 0 Brightest Per 1803 Zwicky (F) 5 26.7 14.1 -66 1 27.1 0.08 # Name Date Mag Dec (h) Amp. U 178 Belisana (F) 5 28.0 11.9 -22 2 12.321 0.18 ------15754 1992 EP (F) 5 28.1 15.0 -21 0 324 Bamberga 4 03.0 12.0 -15 29.43 0.07 3 4554 Fanynka (F) 5 29.7 15.0 -24 0 747 Winchester 4 08.1 13.3 +13 9.402 0.08-0.13 4 6845 Mansurova (F) 5 31.2 15.0 -14 0 125 Liberatrix 4 10.3 12.4 -04 3.968 0.20-0.71 4 774 Armor (F) 5 31.3 11.6 -22 2+ 25.162 0.34 683 Lanzia 5 04.1 12.4 -32 8.630 0.12 3 596 Scheila (F) 6 01.6 11.6 -22 2 15.848 0.09 79 Eurynome 5 10.4 11.8 -15 5.978 0.05-0.24 4 1782 Schneller (F) 6 02.3 14.6 -20 1 >0.6 238 Hypatia 6 04.2 12.6 -05 8.86 0.12-0.15 4 4597 Consolmagno (F) 6 03.2 14.5 -23 0 505 Cava 6 06.1 13.2 -19 8.1789 0.15-0.23 3 456 Abnoba (F) 6 04.1 11.9 -12 2 18.203 0.24 804 Hispania 6 28.1 11.5 -47 14.845 0.19-0.24 3 13374 1998 VT10 (F) 6 06.1 14.7 -26 0 677 Aaltje (F) 6 06.2 13.5 -27 1 >10.0 <0.1 1044 Teutonia (F) 6 07.5 13.2 -25 0 2180 Marjaleena (F) 6 07.5 14.8 -17 0 Radar-Optical Opportunities 6932 Tanigawadake (F) 6 08.0 14.8 -18 0 1823 Gliese (F) 6 08.2 14.4 -28 0 2006 VV2 5632 Ingelehmann (F) 6 08.9 14.5 -20 0 No known lightcurve parameters. 17152 1999 JA118 (F) 6 09.0 14.8 -21 0 1124 Stroobantia (F) 6 09.1 14.5 -33 1 16.39 0.15 Date Geocentric 6045 1991 RG9 (F) 6 10.0 14.8 -18 0 mm/dd RA(2000) DC(2000) V PA E 34548 2000 SY237 (F) 6 10.9 15.0 -27 0 ------6012 1990 SK4 (F) 6 11.9 14.9 -35 0 03/15 23 30.24 +70 26.9 16.04 98.0 73 153 Hilda (F) 6 12.7 12.2 -17 2 5.11 0.05 03/25 0 56.40 +82 15.2 14.05 95.4 81 7405 1988 FF (F) 6 15.8 14.5 -24 0 03/30 10 14.59 +54 43.1 10.92 63.5 115 2724 Orlov (F) 6 15.8 15.0 -17 0 04/09 11 01.34 -48 03.1 13.20 45.3 131 3698 Manning (F) 6 17.2 14.9 -18 0 04/19 11 13.11 -54 54.2 14.94 45.6 127 1881 Shao (F) 6 18.6 15.0 -12 0 04/30 11 26.43 -56 07.8 16.01 42.5 126 7134 Ikeuchisatoru (F) 6 19.5 14.8 - 8 0 5081 Sanguin (F) 6 21.6 14.0 -27 0 3484 Neugebauer (F) 6 24.0 15.0 -11 0 1775 Zimmerwald (F) 6 24.3 14.7 + 0 ? 1862 Apollo (Binary) 2554 Skiff (F) 6 24.9 14.5 -28 0 The lightcurve has a period of 3.065 hr, amplitude 0.15-1.15mag. 3713 Pieters (F) 6 26.1 14.9 -18 0 Apollo is of particular interest because additional lightcurves, 1954 Kukarkin (F) 6 27.2 14.1 -25 0 1064 Aethusa (F) 6 27.5 12.5 -25 2 8.621 0.18 combined with radar data, could provide a wealth of information. For example, how well do lightcurves predict the shape in comparison to radar imaging, the effects of YORP (thermal re- radiation) on the asteroids rotation rate, and mass/density Low Phase Angle Opportunities estimates that can be compared against the satellite's behavior. # Name Date α V Dec ------Date Geocentric 189 Phthia 04 03.4 0.62 12.4 -07 mm/dd RA(2000) DC(2000) V PA E 872 Holda 04 04.1 0.12 12.9 -06 ------147 Protogeneia 04 07.2 0.68 12.7 -09 04/10 15 53.42 -17 34.4 15.85 30.5 140 150 Nuwa 04 09.9 0.12 12.7 -08 04/20 16 20.64 -21 36.6 14.79 31.0 142 56 Melete 04 11.8 0.75 11.3 -07 04/30 17 31.99 -31 14.8 13.56 40.9 135 615 Roswitha 04 15.1 0.37 13.2 -10 05/10 22 55.03 -35 22.0 14.17 96.5 79 743 Eugenisis 04 22.8 0.74 13.9 -14 05/15 1 03.52 -18 35.6 16.41 124.3 51 106 Dione 04 24.0 0.83 12.6 -10 384 Burdigala 04 28.3 0.55 13.4 -13 796 Sarita 04 29.5 0.86 13.5 -17 2005 NW44 379 Huenna 05 01.5 0.52 13.6 -13 No known lightcurve parameters. 62 Erato 05 02.6 0.83 13.9 -12 79 Eurynome 05 10.4 0.94 11.8 -15 Date Geocentric 1186 Turnera 05 12.2 0.72 13.3 -20 mm/dd RA(2000) DC(2000) V PA E 1388 Aphrodite 05 18.0 0.21 12.7 -20 ------229 Adelinda 05 19.0 0.42 13.9 -21 06/19 19 01.28 +34 01.0 16.54 57.2 120 1110 Jaroslawa 05 19.9 0.38 13.4 -20 06/21 18 17.15 +26 45.6 16.38 47.9 130 378 Holmia 05 20.5 0.39 13.9 -19 06/23 17 42.63 +19 35.1 16.37 40.9 137 270 Anahita 05 23.7 0.46 10.8 -21 06/25 17 16.15 +13 11.5 16.48 36.7 141 321 Florentina 05 27.1 0.55 14.0 -23 06/26 17 05.32 +10 22.4 16.58 35.5 142 178 Belisana 05 28.0 0.37 12.0 -22 21 Lutetia 05 31.1 0.49 9.9 -21 1115 Sabauda 05 31.1 0.34 13.8 -21 774 Armor 05 31.3 0.15 11.7 -22 596 Scheila 06 01.6 0.18 11.7 -22 423 Diotima 06 02.1 0.18 11.1 -23 245 Vera 06 02.2 0.36 12.6 -23

Minor Planet Bulletin 34 (2007) 52

BRIAN WARNER WINS 2006 THE MINOR PLANET BULLETIN (ISSN 1052-8091) is the quarterly CHAMBLISS AMATEUR ACHIEVEMENT MEDAL journal of the Minor Planets Section of the Association of Lunar and Planetary Observers – ALPO. Beginning with volume 32, the current and The American Astronomical Society (AAS) has awarded the most recent issues of the MPB are available on line, free of charge at http://www.minorplanetobserver.com/mpb/default.htm . Subscription Chambliss Amateur Achievement Medal for 2006 to MPB information for conventional printed copies is given below. Assistant Editor Brian D. Warner. This award, being given for the first time, is named for Carlson R. Chambliss (Kutztown Nonmembers are invited to join ALPO by communicating with: Matthew University, Pennsylvania), who donated the funds to support L. Will, A.L.P.O. Membership Secretary, P.O. Box 13456, Springfield, IL several new AAS prizes. The AAS cited Warner “for his many 62791-3456 ([email protected]). The Minor Planets Section is contributions to the photometric study of asteroids. His skillful, directed by its Coordinator, Prof. Frederick Pilcher, 4438 Organ Mesa methodical observations using multiple CCD-equipped telescopes Loop, Las Cruces, NM 88011 USA ([email protected]), assisted by Lawrence Garrett, 206 River Road, Fairfax, VT 05454 USA at Palmer Divide Observatory have resulted in the publication of ([email protected]). Steve Larson, Lunar and Planetary Laboratory, more than 200 asteroid lightcurves. His discovery of numerous 1629 E. University Blvd., University of Arizona, Tucson, AZ 85721 USA binaries in the main belt has overturned the idea that binary ([email protected]) is Scientific Advisor. The Asteroid Photometry asteroids form only through tidal interactions with planets. Warner Coordinator is Brian D. Warner, Palmer Divide Observatory, 17995 encourages and supports other asteroid observers, both amateur Bakers Farm Rd., Colorado Springs, CO 80908 USA and professional, through his ongoing development of the software ([email protected]). MPO Canopus, his regular writing in the Minor Planet Bulletin, and his book A Practical Guide to Lightcurve Photometry and The Minor Planet Bulletin is edited by Dr. Richard P. Binzel, MIT 54-410, Analysis, now in its second edition (Springer, 2006). His efforts Cambridge, MA 02139 USA ([email protected]). Brian D. Warner (address above) is Assistant Editor. The MPB is produced by Dr. Robert A. have facilitated a 21st-century renaissance in precision Werner, JPL MS 301-150, 4800 Oak Grove Drive, Pasadena, CA 91109 measurements of asteroid lightcurves.” From all of your friends USA ([email protected]) and distributed by Derald D. Nye. and readers of the Minor Planet Bulletin, congratulations Brian on an award and recognition that are truly well deserved! The contact for all subscriptions, contributions, address changes, etc. is:

Mr. Derald D. Nye Minor Planet Bulletin 10385 East Observatory Drive CALL FOR OBSERVATIONS Corona de Tucson, AZ 85641-2309 USA ([email protected]) Frederick Pilcher (Telephone: 520-762-5504) 4438 Organ Mesa Loop Las Cruces, NM 88011 USA Annual subscription rates for the Minor Planet Bulletin by postal delivery: [email protected] Payment Payment by Observers who have made visual, photographic, or CCD by check credit card measurements of positions of minor planets in calendar 2006 are North America $14.00 $15.00 encouraged to report them to this author on or before April 1, All other $19.00 $20.00 2007. This will be the deadline for receipt of reports which can be To minimize our administrative time, please consider subscribing for two included in the “General Report of Position Observations for years. Users of the on-line MPB who are not paid subscribers are 2006,” to be published in MPB Vol. 34, No. 3. encouraged to make a voluntary contribution of $5 or more per year. Checks or money orders should be in US dollars, drawn on a US bank, and made payable to the “Minor Planet Bulletin.” To pay by credit card, (Visa, Mastercard, or Discover) please send by mail your credit card number, ERRATUM your name exactly as it appears on the card, and the expiration date. Be sure to specify the desired length of your subscription. Credit card charges Higgins, D., and Goncalves, R. (2007). “Asteroid Rotational will be made through “Roadrunner Mkt, Corona AZ.” When sending your subscription order, be sure to include your full mailing address and an Lightcurve Analysis at Hunters Hill Observatory and email address, if available. The numbers in the upper-right corner of your Collaborating Stations – June-September 2006.” MPB 34, 16-18. mailing label indicate the volume and issue number with which your current subscription expires. The period tabulated for asteroid 2510 Shandong should read: 5.9463 ± 0.0003 hr and the amplitude 0.44 mag. The lightcurve Authors are strongly encouraged to submit their manuscripts by electronic figure presented for 2510 Shandong is correct as published. mail ([email protected]). Electronic submissions can be formatted either using a Microsoft Word template document available at the web page given above, or else as text-only. A printed version of the file and figures must also be sent. All materials must arrive by the deadline for each issue. Visual photometry observations, positional observations, any type of observation not covered above, and general information requests should be sent to the Coordinator.

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Minor Planet Bulletin 34 (2007)