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. Author manuscript; available in PMC: 2020 May 26.
Published in final edited form as: Minor Planet Bull. 2013 Oct-Dec;40(4):236–240.

LIGHTCURVE PHOTOMETRY OPPORTUNITIES: 2013 OCTOBER-DECEMBER

Brian D Warner 1, Alan W Harris 2, Petr Pravec 3, Josef Ďurech 4, Lance AM Benner 5
PMCID: PMC7249614  NIHMSID: NIHMS1569917  PMID: 32457954

Abstract

We present lists of asteroid photometry opportunities for objects reaching a favorable apparition and have no or poorly-defined lightcurve parameters. Additional data on these objects will help with shape and spin axis modeling via lightcurve inversion. We also include lists of objects that will be the target of radar observations. Lightcurves for these objects can help constrain pole solutions and/or remove rotation period ambiguities that might not come from using radar data alone.

We present lists of “targets of opportunity” for the period 2013 October-December. For background on the program details for each of the opportunity lists, refer to previous issues, e.g., Minor Planet Bulletin 36, 188. In the first three sets of tables, “Dec” is the declination and “U” is the quality code of the lightcurve. See the asteroid lightcurve data base (LCDB) documentation for an explanation of the U code:

http://www.minorplanet.info/lightcurvedatabase.html

Objects with U = 1 should be given higher priority over those rated U = 2 or 2+ but not necessarily over those with no period. On the other hand, do not overlook asteroids with U = 2/2+ on the assumption that the period is sufficiently established. Regardless, do not let the existing period influence your analysis since even high quality ratings have been proven wrong at times. Note that the lightcurve amplitude in the tables could be more or less than what’s given. Use the listing only as a guide.

The first list is an abbreviated list of those asteroids reaching V < 15.0 at brightest during the period and have either no or poorly-constrained lightcurve parameters.

The goal for these asteroids is to find a well-determined rotation rate. The target list generator on the CALL web site allows you to create custom lists for objects reaching V ≤ 18.0 during any month in the current year, e.g., limiting the results by magnitude and declination.

http://www.minorplanet.info/PHP/call_OppLCDBQuery.php

In a general note, small objects with periods up to 4 hours or even longer are possible binaries. For longer periods (4–6 hours or so), the odds of a binary may be less, but the bonus is that the size of the secondary, if it exists, is likely larger (see Pravec et al. (2010), Nature 466, 1085–1088), thus eclipses, if they occur, will be deeper and easier to detect.

The Low Phase Angle list includes asteroids that reach very low phase angles. The “α” column is the minimum solar phase angle for the asteroid. Getting accurate, calibrated measurements (usually V band) at or very near the day of opposition can provide important information for those studying the “opposition effect.” You will have the best chance of success working objects with low amplitude and periods that allow covering, e.g., a maximum, every night. Objects with large amplitudes and/or long periods are much more difficult for phase angle studies since, for proper analysis, the data have to be reduced to the average magnitude of the asteroid for each night. Without knowing the period and/or the amplitude at the time, that reduction becomes highly uncertain. As an aside, some use the maximum light to find the phase slope parameter (G). However, this can produce a significantly different value for both H and G versus using average light, which is the method used for values listed by the Minor Planet Center.

The third list is of those asteroids needing only a small number of lightcurves to allow spin axis and/or shape modeling. Those doing work for modeling should contact Josef Ďurech at the email address above and/or visit the Database of Asteroid Models from Inversion Techniques (DAMIT) web site for existing data and models:

http://astro.troja.mff.cuni.cz/projects/asteroids3D

The fourth list gives a brief ephemeris for planned radar targets. Supporting optical observations to determine the lightcurve period, amplitude, and shape are needed to supplement the radar data. High-precision work, 0.01–0.02 mag, is preferred, especially if the object is a known or potential binary. Those obtaining lightcurves in support of radar observations should contact Dr. Benner directly at the email given above.

Future radar targets:

http://echo.jpl.nasa.gov/~lance/future.radar.nea.periods.html

Past radar targets:

http://echo.jpl.nasa.gov/~lance/radar.nea.periods.html

Arecibo targets:

http://www.naic.edu/~pradar/sched.shtml

http://www.naic.edu/~pradar

Goldstone targets:

http://echo.jpl.nasa.gov/asteroids/goldstone_asteroid_schedule.html

As always, we encourage observations of asteroids even if they have well-established lightcurve parameters and especially if they are lacking good spin axis and/or shape model solutions. Every lightcurve of sufficient quality supports efforts to resolve a number of questions about the evolution of individual asteroids and the general population. For example, pole directions are known for only about 30 NEAs out of a population of 8000. This is hardly sufficient to make even the most general of statements about NEA pole alignments, including whether or not the thermal YORP effect is forcing pole orientations into a limited number of preferred directions (see La Spina et al., 2004, Nature 428, 400–401). Data from many apparitions can help determine if an asteroid’s rotation rate is being affected by YORP, which can also cause the rotation rate of a smaller, irregularly-shaped asteroid to increase or decrease. See Lowry et al. (2007) Science 316, 272–274 and Kaasalainen et al. (2007) Nature 446, 420–422.

The ephemeris listings for the optical-radar listings include lunar elongation and phase. Phase values range from 0.0 (new) to 1.0 (full). If the value is positive, the moon is waxing – between new and full. If the value is negative, the moon is waning – between full and new. The listing also includes the galactic latitude. When this value is near 0°, the asteroid is likely in rich star fields and so may be difficult to work. It is important to emphasize that the ephemerides that we provide are only guides for when you might observe a given asteroid. Obviously, you should use your discretion and experience to make your observing program as effective as possible.

Once you’ve analyzed your data, it’s important to publish your results. Papers appearing in the Minor Planet Bulletin are indexed in the Astrophysical Data System (ADS) and so can be referenced by others in subsequent papers. It’s also important to make the data available at least on a personal website or upon request.

Lightcurve Opportunities

Objects in bold italics are near-Earth asteroids (NEA), defined as q < 1.3 AU. An asterisk (*) follows the name if the asteroid is reaching a particularly favorable apparition.

Brightest LCDB Data
# Name Date Mag Dec Period Amp U
2771 Polzunov* 10 02.2 14.7 +11 11.66 0.15 2
4517 Ralpharvey 10 02.9 14.4 +1
1180 Rita 10 03.3 14.4 −5 9.605 0.05–0.30 2
2212 Hephaistos 10 05.2 14.0 −44 > 20. 0.08–0.11 1
9199 1993 FO1* 10 06.3 15.0 −3 5.322 0.47 2+
2286 Fesenkov* 10 06.6 14.5 +3
828 Lindemannia 10 07.9 14.5 +6 0.08
6634 1987 KB 10 07.9 14.4 +21 4.492 0.22 2
1653 Yakhontovia* 10 08.3 12.7 +14 15.41 0.03 2
2259 Sofievka 10 08.3 14.8 +14 31.6 0.10 2
1070 Tunica 10 08.4 14.8 −6
2443 Tomeileen 10 10.0 14.7 −8 3.974 0.10–0.13 2
712 Boliviana 10 11.0 10.9 +18 11.732 0.10–0.11 2
1428 Mombasa 10 11.8 13.7 −19 16.67 0.15–0.25 2+
2660 Wasserman 10 13.0 14.9 +9 0.07
1246 Chaka* 10 13.6 13.0 +40 > 20. 0.2 2
3330 Gantrisch 10 15.7 14.8 +12
1557 Roehla 10 16.9 15.0 +17
7288 1991 FE1* 10 16.9 14.8 +15
641 Agnes* 10 17.2 13.9 +8 8.9 0.18 1
2112 Ulyanov* 10 17.3 13.9 +13 3. 0.33 2
4905 Hiromi* 10 17.8 14.2 +7
3250 Martebo* 10 18.0 14.5 +9
1359 Prieska 10 18.1 14.4 −1 0.04
1384 Kniertje 10 18.2 14.4 −6 9.807 0.11–0.33 2
3062 Wren* 10 21.2 14.5 −6 7.097 0.17–0.22 2
1639 Bower 10 23.5 13.7 +24 12.5 0.15–0.38 2
16009 1999 CM8* 10 23.5 14.0 +7
2281 Biela 10 23.8 15.0 +11
5110 Belgirate* 10 23.8 15.0 +18 11.04 0.08 1
983 Gunila 10 25.7 14.5 +25 D 0.05–0.25
3500 Kobayashi 10 25.7 14.5 +21
7167 Laupheim* 10 26.0 15.0 +17
691 Lehigh 10 26.4 12.9 −4 12.891 0.12–0.16 2+
1457 Ankara 10 26.9 15.0 +21 31.8 0.21 2
1305 Pongola 10 27.0 15.0 +11 8.03 0.14–0.18 2
2254 Requiem 10 27.3 14.3 +21
1167 Dubiago 11 01.0 14.5 +15 14.3 0.23 2
1447 Utra* 11 01.0 14.5 +15 257. 0.63 2
5256 Farquhar 11 01.2 14.5 +15 0.04
2305 King* 11 02.3 14.9 +18
445 Edna 11 03.9 13.2 +45 19.97 0.21 2
425 Cornelia 11 05.2 13.6 +14 17.56 0.19 2
1079 Mimosa 11 05.6 14.5 +17 64.6 0.07–0.13 2
941 Murray* 11 05.8 13.9 +14
8648 Salix* 11 09.0 14.5 +14
431 Nephele 11 09.2 12.6 +14 18.821 0.03–0.30 2
2325 Chernykh* 11 09.3 15.0 +14
3905 Doppler* 11 09.4 14.6 +41
583 Klotilde 11 10.3 13.5 +23 9.2116 0.18–0.41 2
3248 Farinella 11 12.5 15.0 +28 6.676 0.20 2
2280 Kunikov 11 14.3 14.7 +13
1603 Neva 11 14.4 14.1 +5 6.4249 0.22 2
2077 Kiangsu* 11 14.4 14.8 −14
1033 Simona 11 14.6 14.7 +7 10.07 0.04 1+
1233 Kobresia 11 14.7 14.9 +26 27.83 0.32–0.34 2
2086 Newell* 11 14.7 14.7 +7 78.2 1.0 2
7355 Bottke* 11 16.0 14.8 +17
507 Laodica 11 16.2 13.2 +31 6.737 0.22–0.29 2
4135 Svetlanov 11 17.6 14.9 +11 10.559 0.15 2
4067 Mikhel’son* 11 17.9 15.0 +30
2053 Nuki* 11 19.3 14.7 +10
3702 Trubetskaya 11 19.4 14.1 −5
1055 Tynka 11 20.0 14.2 +11 11.893 0.06–0.33 2
2675 Tolkien 11 21.2 14.0 +24 1060. 0.75 2+
1911 Schubart 11 21.4 14.9 +22
946 Poesia 11 22.0 13.9 +20 108.5 0.24–0.32 2+
1027 Aesculapia 11 22.7 15.0 +21 6.83 0.15 1
2271 Kiso 11 23.0 14.6 +15 0.12
4649 Sumoto* 11 24.8 14.3 +12 26.31 0.15–0.30 2
2239 Paracelsus 11 25.0 15.0 +32
6246 Komurotoru* 11 25.2 14.4 +31
1887 Virton 11 26.8 14.7 +35
920 Rogeria* 11 27.1 14.3 +6 8.09 0.16–0.21 2−
341 California 11 27.3 13.0 +27 8.74 0.02–0.07 1
2043 Ortutay 11 27.3 14.5 +26
2413 van de Hulst 11 27.5 15.0 +5
3437 Kapitsa* 11 27.5 15.0 +25
1326 Losaka* 11 29.4 13.6 +5 6.9 0.03 2
1112 Polonia 12 01.0 13.8 +33 82.5 0.20 2
786 Bredichina 12 02.3 13.7 +15 18.61 0.05–0.60 2+
1365 Henyey 12 02.3 14.8 +23 18.986 0.23 2+
279 Thule 12 03.1 14.3 +22 15.962 0.04–0.10 2+
1085 Amaryllis 12 04.1 14.4 +14 18.2 0.20 2
1539 Borrelly 12 04.1 14.4 +20
1194 Aletta 12 04.3 14.7 +33 20.39 0.28–0.32 2+
2531 Cambridge 12 04.6 14.9 +13 8.8 0.21 2−
2393 Suzuki 12 05.0 15.0 +15 9.31 0.40 2+
856 Backlunda 12 05.1 14.3 +4 12.08 0.24–0.33 2
2391 Tomita* 12 07.2 14.5 +17
496 Gryphia* 12 10.1 13.5 +17 18. 0.05 1
1574 Meyer* 12 11.0 14.8 +18 12.64 0.12 2
2638 Gadolin* 12 12.5 14.5 +17
560 Delila* 12 14.0 13.6 +17 0.1
365 Corduba 12 15.9 12.5 +3 6.354 0.05–0.15 2
767 Bondia 12 17.7 14.2 +24
666 Desdemona 12 17.8 13.0 +13 15.45 0.07–0.16 2
2536 Kozyrev 12 18.3 14.3 +25 7.188 0.52 2+
707 Steina 12 19.0 14.0 +25 414. 0.1– 1.0 2+
6906 Johnmills* 12 19.2 15.0 +30
1596 Itzigsohn* 12 20.8 13.9 +16 39.722 0.15–0.41 2
537 Pauly 12 21.3 13.7 +16 14.15 0.15–0.20 2+
437 Rhodia 12 23.5 13.7 +22 56. 0.06–0.38 1
318 Magdalena* 12 24.0 13.6 +8 59.5 0.11 1
1191 Alfaterna 12 24.9 14.9 +4 3.664 0.03–0.05 1
1678 Hveen 12 26.3 14.8 +39
1888 Zu Chong-Zhi* 12 27.4 13.8 +18 15.9 0.50 2
703 Noemi 12 27.6 14.2 +19
1826 Miller* 12 28.7 14.5 +23 30.049 0.08 2
1264 Letaba 12 29.3 14.5 −1 32.16 0.11–0.13 1
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Low Phase Angle Opportunities

# Name Date α V Dec Period Amp U
149 Medusa 10 01.9 0.43 12.6 +03 26.023 0.47–0.56 3
641 Agnes 10 17.1 0.52 13.9 +08 8.9 0.18 1
546 Herodias 10 21.1 0.97 13.0 +13 10.77 0.07–0.18 3
1675 Simonida 10 26.9 0.38 13.5 +13 5.2885 0.16–0.65 3
168 Sibylla 10 27.7 0.30 12.2 +12 47.009 0.16 3
326 Tamara 10 28.3 0.79 12.4 +15 14.445 0.10–0.27 3
99 Dike 10 30.3 0.55 13.7 +12 18.127 0.08–0.22 3
798 Ruth 10 30.5 0.23 13.6 +13 8.550 0.19–0.36 3
1074 Beljawskya 10 31.8 0.10 13.3 +14 6.284 0.28–0.37 3
20 Massalia 11 01.0 0.12 8.7 +14 8.098 0.15–0.27 3
425 Cornelia 11 05.2 0.63 13.7 +14 17.56 0.19 2
941 Murray 11 05.8 0.83 14.0 +14
126 Velleda 11 08.1 0.86 11.7 +18 5.3672 0.07–0.22 3
284 Amalia 11 08.5 0.76 13.0 +18 8.545 0.16 3
431 Nephele 11 09.4 0.88 12.6 +14 18.821 0.02–0.30 2
1567 Alikoski 11 12.6 0.23 13.9 +17 16.405 0.16 3
946 Poesia 11 22.0 0.14 14.0 +20 108.5 0.32 2+
76 Freia 11 23.3 0.64 11.8 +19 9.969 0.06–0.33 3
447 Valentine 12 02.3 0.15 12.7 +22 9.651 0.18 3
567 Eleutheria 12 03.0 0.87 13.7 +25 7.72 0.26–0.50 3
138 Tolosa 12 04.2 0.59 11.9 +24 10.101 0.18–0.45 3
64 Angelina 12 06.0 0.72 10.5 +24 8.752 0.04–0.42 3
899 Jokaste 12 07.0 0.33 13.1 +22 6.245 0.25–0.31 3
977 Philippa 12 09.4 0.22 13.8 +23 15.405 0.49 3
405 Thia 12 10.1 0.32 12.1 +22 10.08 0.15–0.23 3
222 Lucia 12 12.7 0.10 14.0 +23 7.80 0.25–0.38 3
535 Montague 12 14.3 0.24 12.4 +23 10.2482 0.18–0.25 3
437 Rhodia 12 23.7 0.65 13.7 +22 56. 0.06–0.38 1
277 Elvira 12 26.8 0.42 13.6 +22 29.69 0.34–0.59 3
3169 Ostro 12 27.3 0.63 13.6 +22 6.483 0.42–1.2 3
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Shape/Spin Modeling Opportunities

There are two lists here. The first is for objects for which good occultation profiles are available. These are used to constrain the models obtained from lightcurve inversion, eliminating ambiguous solutions and fixing the size of asteroid. Lightcurves are needed for modeling and/or to establish the rotation phase angle at the time the profile was obtained. The second list is of those objects for which another set of lightcurves from one more apparitions will allow either an initial or a refined solution.

Occultation Profiles Available

Brightest LCDB DATA
# Name Date Mag De Period Amp U
568 Cheruskia 10 02.1 13.2 +26 13.209 0.10–0.44 3
828 Lindemannia 10 07.9 14.5 +06 0.08
404 Arsinoe 10 13.2 13.5 −10 8.887 0.27–0.38 3
99 Dike 10 30.3 13.6 +12 18.127 0.08–0.22 3
566 Stereoskopia 11 06.2 12.1 +12 12.103 0.05–0.25 3
431 Nephele 11 09.2 12.6 +14 18.821 0.02–0.30 2
76 Freia 11 23.3 11.8 +19 9.969 0.06–0.33 3
134 Sophrosyne 11 26.2 11.6 +40 17.196 0.19 3
638 Moira 12 01.4 14.3 +16 9.875 0.31 3
350 Ornamenta 12 07.6 11.9 +11 9.178 0.10–0.23 3
522 Helga 12 07.6 13.8 +19 8.129 0.13–0.30 3
366 Vincentina 12 09.8 13.3 +38 15.5 0.08 1
120 Lachesis 12 27.6 12.2 +32 46.551 0.14–0.22 3
381 Myrrha 12 28.8 13.2 +15 6.572 0.36 3
18 Melpomene 12 31. 9.8 +08 11.570 0.10–0.32 3
141 Lumen 12 31. 12.5 +23 19.87 0.12–0.2 3
51 Nemausa 12 31. 10.4 +06 7.783 0.10–0.25 3
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Inversion Modeling Candidates

Brightest LCDB Data
# Name Date Mag Dec Period Amp U
482 Petrina 10 01.2 12.9 +00 11.794 0.07–0.45 3−
6634 1987 KB 10 07.9 14.4 +21 4.492 0.22 2
718 Erida 10 25.9 14.6 +11 17.447 0.37 3
1426 Riviera 10 31.5 14.9 +26 4.404 0.30 3
20 Massalia 11 01.0 8.7 +14 8.098 0.15–0.27 3
1691 Oort 11 02.7 14.2 +14 10.2705 0.38 3
214 Aschera 11 06.8 12.4 +21 6.835 0.22 3
3737 Beckman 11 07.0 13.4 +60 3.124 0.16 3
1003 Lilofee 11 11.4 14.3 +15 8.255 0.52 3
1233 Kobresia 11 14.7 14.9 +26 27.83 0.34 2
2086 Newell 11 14.7 14.7 +07 78.2 1.0 2
734 Benda 11 20.7 13.7 +27 7.11 0.28 3
1125 China 11 22.4 14.8 +17 5.367 0.38 3
804 Hispania 11 23.9 11.9 +43 14.845 0.19–0.24 3
656 Beagle 11 24.8 14.1 +20 7.035 0.9 –1.2 3
228 Agathe 11 26.0 14.5 +25 6.484 0.27 3
1204 Renzia 11 29.8 14.3 +24 7.885 0.42 3
274 Philagoria 11 30.8 14.4 +20 17.96 0.43–0.51 3
638 Moira 12 01.4 14.3 +16 9.875 0.31 3
567 Eleutheria 12 03.1 13.6 +25 7.72 0.26–0.50 3
2393 Suzuki 12 05.0 15.0 +15 9.31 0.40 2+
856 Backlunda 12 05.1 14.3 +04 12.08 0.29 2
1797 Schaumasse 12 08.0 15.0 +27 6.105 0.75 3−
744 Aguntina 12 09.5 14.7 +13 17.47 0.50 3
3155 Lee 12 11.4 14.5 +33 8.310 0.22–0.35 3
707 Steina 12 19.0 14.0 +25 414. 0.1 –1.0 2+
537 Pauly 12 21.3 13.7 +16 14.15 0.15–0.20 2+
5489 Oberkochen 12 21.8 14.5 +18 5.625 0.40 3
607 Jenny 12 22.7 13.9 +27 8.526 0.17–0.26 3−
1703 Barry 12 26.2 14.8 +21 107.1 0.5 3
1826 Miller 12 28.7 14.6 +23 30.049 0.08 2
1368 Numidia 12 29.9 14.8 +46 3.64 0.35 3
345 Tercidina 12 31. 11.7 +03 12.371 0.11–0.23 3
317 Roxane 12 31. 13.5 +17 8.169 0.61–0.75 3
1618 Dawn 12 31. 15.0 +23 43.19 0.38 2+
208 Lacrimosa 12 31. 13.7 +13 14.085 0.15–0.33 3
239 Adrastea 12 31. 14.1 +12 18.4707 0.34–0.51 3
271 Penthesilea 12 31. 14.0 +25 18.787 0.33 3
868 Lova 12 31. 14.2 +17 41.3 0.40 2
2381 Landi 12 31. 14.7 +05 3.91 0.75 2
1339 Desagneauxa 12 31. 14.5 +25 9.380 0.48 3
1021 Flammario 12 31. 11.5 +16 12.160 0.14–0.40 3−
1219 Britta 12 31. 13.7 +30 5.575 0.48–0.75 3
616 Elly 12 31. 14.9 +19 5.297 0.34–0.44 3
4299 WIYN 12 31. 14.9 +22 26. 0.06 2
502 Sigune 12 31. 15.0 +06 10.922 0.25–0.53 3
1494 Savo 12 31. 14.3 +18 5.35011 0.45–0.52 3
822 Lalage 12 31. 15.0 +11 3.345 0.47–0.58 3
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Radar-Optical Opportunities

Use the ephemerides below as a guide to your best chances for observing, but remember that photometry may be possible before and/or after the ephemerides given below. Some of the targets may be too faint to do accurate photometry with backyard telescopes. However, accurate astrometry using techniques such as “stack and track” is still possible and can be helpful for those asteroids where the position uncertainties are significant. Note that the intervals in the ephemerides are not always the same and that geocentric positions are given. Use these web sites to generate updated and topocentric positions:

MPC: http://www.minorplanetcenter.org/iau/MPEph/MPEph.html

JPL: http://ssd.jpl.nasa.gov/?horizons

In the ephemerides below, ED and SD are, respectively, the Earth and Sun distances (AU), V is the estimated Johnson V magnitude, and α is the phase angle. SE and ME are the great circles distances (in degrees) of the Sun and Moon from the asteroid. MP is the lunar phase and GB is the galactic latitude. “PHA” in the header indicates that the object is a “potentially hazardous asteroid”, meaning that at some (long distant) time, its orbit might take it very close to Earth.

89 Julia (Oct-Nov, H = 6.6)

The rotation period for this inner main-belt asteroid is 11.38 hours. This makes it difficult for a single station to get complete coverage of the lightcurve without an prolonged campaign. A collaboration involving observers well-separated in longitude would be ideal. The estimated diameter is 151 km.

DATE RA Dec ED SD V α SE ME MP GB
10/01 23 21.6 +22 22 1.14 2.09 9.2 11.8 155 137 −0.16 −36
10/08 23 15.3 +22 04 1.16 2.09 9.3 13.3 151 122 +0.11 −36
10/15 23 10.5 +21 37 1.19 2.09 9.4 15.4 146 32 +0.82 −35
10/22 23 07.3 +21 05 1.23 2.10 9.6 17.5 141 70 −0.91 −36
10/29 23 06.0 +20 32 1.28 2.10 9.7 19.6 135 147 −0.31 −36
11/05 23 06.5 +20 00 1.34 2.11 9.9 21.4 129 111 +0.03 −36
11/12 23 08.7 +19 33 1.40 2.11 10.0 23.0 123 23 +0.69 −37
11/19 23 12.5 +19 13 1.47 2.12 10.2 24.3 118 77 −0.98 −38
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216 Kleopatra (Oct-Jan, H = 7.30)

This is the “dog bone” asteroid, so-called because of it shape. The period and even shape are well determined. It’s included here because it often helps to have supporting lightcurve observations to go with the latest radar data. It’s also an excellent teaching object of the high amplitude lightcurve, brightness, and ability to get a complete cycle (or more) in a single night’s run.

DATE RA Dec ED SD V α SE ME MP GB
10/01 03 52.0 +19 18 1.33 2.10 10.4 22.1 128 80 −0.16 −26
10/15 03 53.3 +17 17 1.23 2.10 10.1 17.1 142 88 +0.82 −27
10/29 03 48.2 +14 44 1.16 2.11 9.8 10.7 157 89 −0.31 −30
11/12 03 38.7 +11 58 1.14 2.12 9.5 4.3 171 74 +0.69 −34
11/26 03 28.0 +09 26 1.16 2.13 9.7 6.8 165 103 −0.48 −37
12/10 03 19.9 +07 35 1.24 2.15 10.1 13.3 150 58 +0.54 −40
12/24 03 16.9 +06 38 1.35 2.17 10.4 18.6 135 114 −0.65 −41
01/07 03 19.5 +06 30 1.50 2.19 10.8 22.4 122 49 +0.38 −41
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324 Bamberga (Oct-Nov, H = 6.82)

This middle main-belt asteroid has an estimated diameter of 230 km. It’s a type CP (Tholen, 1989), meaning is has a lower albedo on the order of 0.06. The rotation period of 29.4 h makes this another object where a collaboration among observers will have the best chance of securing a complete lightcurve.

DATE RA Dec ED SD V α SE ME MP GB
10/01 22 56.0 +06 48 0.83 1.79 8.5 12.8 157 152 −0.16 −46
10/06 22 52.9 +07 05 0.84 1.79 8.6 15.4 152 141 +0.01 −45
10/11 22 50.8 +07 22 0.86 1.79 8.8 17.9 147 71 +0.39 −45
10/16 22 49.6 +07 38 0.89 1.78 8.9 20.2 142 10 +0.90 −44
10/21 22 49.5 +07 54 0.92 1.78 9.0 22.3 137 66 −0.96 −44
10/26 22 50.4 +08 11 0.95 1.78 9.2 24.1 133 125 −0.59 −44
10/31 22 52.3 +08 29 0.98 1.78 9.3 25.8 129 168 −0.14 −44
11/05 22 55.1 +08 50 1.02 1.78 9.4 27.2 125 105 +0.03 −44
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1627 Ivar (Oct-Dec, H = 13.2)

This near-Earth asteroid (NEA) is well-placed for most of the quarter. It’s not quite as bright as earlier this year, but still be careful about overexposing it, at least in October. The period is well-known: 4.798 h. The amplitude has ranged from 0.25 to 1.4 mag.

DATE RA Dec ED SD V α SE ME MP GB
10/01 02 06.8 −12 46 0.44 1.40 12.7 20.4 151 111 −0.16 −67
10/11 01 54.0 −13 51 0.48 1.45 12.9 16.3 156 106 +0.39 −70
10/21 01 41.8 −13 57 0.54 1.51 13.2 15.9 155 39 −0.96 −72
10/31 01 32.4 −13 11 0.62 1.56 13.6 18.4 150 147 −0.14 −73
11/10 01 26.7 −11 46 0.71 1.61 14.1 21.7 143 65 +0.48 −73
11/20 01 25.0 −09 56 0.81 1.67 14.5 24.6 135 68 −0.95 −71
11/30 01 26.8 −07 51 0.93 1.72 14.9 27.0 128 160 −0.12 −69
12/10 01 31.7 −05 39 1.06 1.77 15.3 28.7 120 32 +0.54 −66
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(85774) 1998 UT18 (Oct-Dec, H = 19.2)

Krugly et al. (2002; Icarus 158, 294–304) reported a period of 34 hours for this NEA but the result is considered likely wrong (U = 1 in the LCDB). Skiff et al. (2012); (MPB 39, 111–130) reported only an amplitude of 0.34 mag. Don’t let past results influence your analysis. Given past results, it might be wise to collaborate with observers at widely-separated longitudes.

DATE RA Dec ED SD V α SE ME MP GB
10/20 05 55.3 +00 15 0.31 1.16 18.8 50.8 115 54 −0.99 −12
10/27 06 27.9 +02 37 0.26 1.13 18.5 53.5 114 30 −0.50 −4
11/03 07 08.7 +06 02 0.22 1.09 18.2 57.3 112 105 +0.00 +7
11/10 08 00.9 +10 38 0.19 1.06 18.0 62.8 107 165 +0.48 +20
11/17 09 06.1 +15 56 0.18 1.03 18.0 70.0 100 87 +1.00 +37
11/24 10 20.3 +20 33 0.17 1.01 18.1 77.9 92 23 −0.67 +55
12/01 11 32.7 +23 11 0.19 0.99 18.5 84.5 85 59 −0.06 +72
12/08 12 34.1 +23 46 0.21 0.97 18.8 88.6 79 136 +0.32 +85
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(138095) 2000 DK79 (Oct-Dec, H = 15.8)

This NEA has no reported lightcurve parameters in the LCDB. Assuming pV = 0.2, the estimated size if about 2 km. This asteroid makes the celestial rounds, going from far south to far north of the celestial equator during the last three months of the year.

DATE RA Dec ED SD V α SE ME MP GB
10/01 07 08.9 −53 44 0.73 1.15 17.5 59.7 82 70 −0.16 −19
10/15 06 48.4 −57 00 0.50 1.09 16.8 65.6 87 105 +0.82 −23
10/29 05 05.3 −62 55 0.26 1.06 15.4 68.9 97 89 −0.31 −36
11/12 22 57.4 −15 55 0.13 1.04 13.7 63.5 110 13 +0.69 −61
11/26 21 21.2 +31 13 0.32 1.05 15.9 70.5 92 141 −0.48 −13
12/10 20 58.3 +40 45 0.56 1.07 17.0 65.6 83 53 +0.54 −3
12/24 20 51.2 +45 15 0.78 1.12 17.6 59.2 78 125 −0.65 +1
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2007 CN26 (Oct-Nov, H = 21.0, PHA)

There is no reported rotation period in the LCDB. 2007 CN26 is an NEA with an estimated diameter of 200 meters. This puts it on the edge of being a candidate for having a period of less than 2 hours. Statler et al. (2013; Icarus 225, 141–155) report that 170 meters is about the upper limit with the number of faster rotators dropping rapidly at larger sizes. Until you know one way or the other, keep exposures to a minimum but long enough to avoid letting scintillation noise dominate (~10 sec for small telescopes).

DATE RA Dec ED SD V α SE ME MP GB
10/01 02 04.9 −21 52 0.14 1.12 18.1 30.3 146 112 −0.16 −72
10/02 02 03.0 −22 01 0.14 1.12 18.1 29.7 146 122 −0.10 −73
10/03 02 01.0 −22 08 0.15 1.13 18.2 29.2 147 132 −0.05 −73
10/04 01 59.2 −22 14 0.15 1.13 18.2 28.7 147 140 −0.01 −74
10/05 01 57.3 −22 19 0.16 1.13 18.3 28.3 148 145 +0.00 −74
10/06 01 55.6 −22 22 0.16 1.14 18.3 27.8 148 146 +0.01 −75
10/07 01 53.9 −22 25 0.16 1.14 18.4 27.5 148 142 +0.05 −75
10/08 01 52.2 −22 26 0.17 1.15 18.5 27.2 148 135 +0.11 −75
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(52760) 1998 ML14 (Nov-Jan, H = 17.6, PHA)

Hicks et al. (1998; B.A.A.S. 30, 1029) reported a period of 14.98 hours for this NEA estimated to have an effective diameter of about 1 km (Ostro et al. 2001; Meteoritics and Planetary Sci. 36, 1225–1236). It’s not exceptionally bright but it should be within reach of larger backyard telescopes. For northern observers at least, the high declination will mean long runs, which may help find a reliable solution sooner than later.

DATE RA Dec ED SD V α SE ME MP GB
11/10 08 00.3 +28 01 0.40 1.19 17.8 51.0 111 158 +0.48 +27
11/17 07 51.6 +28 25 0.42 1.25 17.8 43.4 120 67 +1.00 +25
11/24 07 39.7 +28 50 0.44 1.31 17.7 35.7 129 24 −0.67 +23
12/01 07 25.1 +29 11 0.46 1.37 17.7 27.9 140 113 −0.06 +20
12/08 07 08.8 +29 23 0.49 1.43 17.7 20.1 150 138 +0.32 +16
12/15 06 52.0 +29 24 0.53 1.49 17.7 12.7 161 46 +0.95 +13
12/22 06 36.2 +29 13 0.57 1.55 17.7 6.2 170 44 −0.82 +10
12/29 06 22.4 +28 52 0.63 1.61 17.9 3.6 174 134 −0.16 +7
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1997 WQ23 (Nov-Dec, H = 20.3)

The estimated size of this NEA (assuming pV = 0.2) is about 250 meters. As with 2007 CN26, this asteroid could have a rotation period under 2 hours. The LCDB does not have a reported period.

DATE RA Dec ED SD V α SE ME MP GB
11/10 21 43.8 −20 51 0.08 1.00 17.7 81.7 94 14 +0.48 −47
11/13 22 47.2 −13 20 0.08 1.02 17.2 68.2 108 20 +0.79 −58
11/16 23 43.8 −05 19 0.08 1.03 17.0 55.4 121 41 +0.97 −63
11/19 00 29.6 +01 34 0.10 1.05 17.1 45.2 131 65 −0.98 −61
11/22 01 05.0 +06 50 0.11 1.07 17.2 38.0 138 91 −0.83 −56
11/25 01 32.3 +10 41 0.13 1.09 17.5 33.2 143 118 −0.58 −51
11/28 01 53.5 +13 29 0.15 1.11 17.7 30.2 145 150 −0.29 −47
12/01 02 10.4 +15 34 0.17 1.14 18.0 28.3 147 173 −0.06 −43
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2006 CT (Dec-Jan, H = 22.3)

At only 100 meters diameter, this is the smallest object included this time, and reason that it is not very bright. Because of the wide range of phase angles, there is an excellent chance to get a series of lightcurves that show amplitude and/or shape evolution from late December into 2014 January. The LCDB has no period.

DATE RA Dec ED SD V α SE ME MP GB
12/25 09 56.3 +19 07 0.07 1.03 18.5 48.5 128 33 −0.56 +49
12/30 09 15.3 +18 52 0.08 1.05 18.4 34.6 143 108 −0.09 +40
01/04 08 41.3 +18 23 0.09 1.07 18.4 22.4 155 167 +0.10 +32
01/09 08 13.9 +17 50 0.11 1.09 18.4 12.1 167 93 +0.59 +26
01/14 07 52.6 +17 20 0.12 1.11 18.4 4.3 175 27 +0.96 +21
01/19 07 36.5 +16 55 0.14 1.13 18.8 6.3 173 36 −0.93 +17
01/24 07 24.7 +16 37 0.16 1.14 19.4 12.3 166 101 −0.52 +15
01/29 07 16.5 +16 24 0.19 1.16 19.9 17.8 159 173 −0.06 +13
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2009 WZ104 (Dec-Jan, H = 20.0)

Karashevich et al. (2012; Solar System Research 46, 143–148) reported a period of 19.304 hours, but could not formally exclude the half-period of 9.652 hours. Be prepared for either possibility.

DATE RA Dec ED SD V α SE ME MP GB
12/25 11 07.0 −16 23 0.16 1.02 18.6 73.0 98 17 −0.56 +40
12/28 11 10.4 −20 53 0.15 1.02 18.5 73.3 98 44 −0.26 +36
12/31 11 14.0 −25 39 0.15 1.01 18.5 73.9 98 81 −0.03 +32
01/03 11 17.6 −30 40 0.14 1.01 18.4 74.8 97 118 +0.04 +28
01/06 11 21.6 −35 53 0.14 1.01 18.4 75.9 96 143 +0.28 +24
01/09 11 25.9 −41 15 0.14 1.00 18.4 77.3 95 137 +0.59 +19
01/12 11 30.8 −46 44 0.14 1.00 18.4 79.1 93 116 +0.85 +14
01/15 11 36.6 −52 14 0.14 1.00 18.5 81.0 91 94 +0.99 +9
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Contributor Information

Brian D. Warner, Palmer Divide Observatory/MoreData!, 17995 Bakers Farm Rd., Colorado Springs, CO 80908 USA

Alan W. Harris, MoreData!, La Cañada, CA 91011-3364 USA

Petr Pravec, Astronomical Institute, CZ-25165 Ondřejov, CZECH REPUBLIC.

Josef Ďurech, Astronomical Institute, Charles University in Prague, 18000 Prague, CZECH REPUBLIC.

Lance A.M. Benner, Jet Propulsion Laboratory, Pasadena, CA 91109-8099 USA

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