4902 Thessandrus
Discovery [1] | |
---|---|
Discovered by | C. Shoemaker |
Discovery site | Palomar Obs. |
Discovery date | 9 January 1989 |
Designations | |
MPC designation | 4902 Thessandrus |
Pronunciation | the-san'-drəs |
Named after |
Thessander (Greek mythology)[2] |
1989 AN2 · 1985 TK3 | |
Jupiter trojan [3][4] (Greek camp) [5] | |
Orbital characteristics [1] | |
Epoch 31 July 2016 (JD 2457600.5) | |
Uncertainty parameter 0 | |
Observation arc | 62.29 yr (22,753 days) |
Aphelion | 5.4235 AU |
Perihelion | 4.9863 AU |
5.2049 AU | |
Eccentricity | 0.0420 |
11.87 yr (4,337 days) | |
153.63° | |
0° 4m 58.8s / day | |
Inclination | 9.0727° |
170.32° | |
271.34° | |
Jupiter MOID | 0.2003 AU |
Jupiter Tisserand parameter | 2.9730 |
Physical characteristics | |
Dimensions |
±0.66 km 51.26[6] 61.04 km (calculated)[4] |
±20 738h[7] | |
0.057 (assumed)[4] ±0.012 0.081[6] | |
D [8] · C [4] | |
±0.52 9.75[8] 9.8[1][4][6] | |
|
4902 Thessandrus (the-san'-drəs), provisionally designated 1989 AN2, is a rare-type Jupiter trojan from the Greek camp and an exceptionally slow rotator, approximately 60 kilometers in diameter. It was discovered on 9 January 1989, by American astronomer Carolyn Shoemaker at the U.S. Palomar Observatory in California.[3]
The S-type asteroid is also classified as a rare D-type asteroid by Pan-STARRS large-scale survey.[8] It orbits the Sun at a distance of 5.0–5.4 AU once every 11 years and 10 months (4,337 days). Its orbit has an eccentricity of 0.04 and an inclination of 9° with respect to the ecliptic.[1] The first precovery was taken at the discovering observatory in 1954, extending the asteroid's observation arc by 35 years prior to its discovery.[3]
In February 2013, a rotational light-curve was obtained from photometric observations by American astronomer Robert D. Stevens at the Center for Solar System Studies in California. It gave an exceptionally long rotation period of ±20 hours with a brightness variation of 0.60 in 738magnitude (U=2).[7]
According to the survey carried out by the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, the asteroid measures 51.3 kilometers in diameter and its surface has an albedo of 0.081,[6] while the Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a somewhat larger diameter of 61.0 kilometers, as the lower the albedo (reflectivity), the larger the body's diameter, at a constant absolute magnitude (brightness).[4]
The Jovian asteroid is named after Thessander (Thessandrus) from Greek mythology and Homer's Iliad. Together with 30 other Greek soldiers he hid in the Trojan horse's belly.[2] Naming citation was published on 4 June 1993 (M.P.C. 22248).[9]
References
- 1 2 3 4 "JPL Small-Body Database Browser: 4902 Thessandrus (1989 AN2)" (2016-06-13 last obs.). Jet Propulsion Laboratory. Retrieved 30 June 2016.
- 1 2 Schmadel, Lutz D. (2007). Dictionary of Minor Planet Names – (4902) Thessandrus. Springer Berlin Heidelberg. p. 423. ISBN 978-3-540-00238-3. Retrieved 30 June 2016.
- 1 2 3 "4902 Thessandrus (1989 AN2)". Minor Planet Center. Retrieved 30 June 2016.
- 1 2 3 4 5 6 "LCDB Data for (4902) Thessandrus". Asteroid Lightcurve Database (LCDB). Retrieved 30 June 2016.
- ↑ "List of Jupiter Trojans". Minor Planet Center. 20 June 2016. Retrieved 30 June 2016.
- 1 2 3 4 Mainzer, A.; Grav, T.; Masiero, J.; Hand, E.; Bauer, J.; Tholen, D.; et al. (November 2011). "NEOWISE Studies of Spectrophotometrically Classified Asteroids: Preliminary Results" (PDF). The Astrophysical Journal. 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved 30 June 2016.
- 1 2 French, Linda M.; Stephens, Robert, D.; Coley, Daniel R.; Wasserman, Lawrence H.; Vilas, Faith; La Rocca, Daniel (October 2013). "A Troop of Trojans: Photometry of 24 Jovian Trojan Asteroids". The Minor Planet Bulletin. 40 (4): 198–203. Bibcode:2013MPBu...40..198F. ISSN 1052-8091. Retrieved 30 June 2016.
- 1 2 3 Veres, Peter; Jedicke, Robert; Fitzsimmons, Alan; Denneau, Larry; Granvik, Mikael; Bolin, Bryce; et al. (November 2015). "Absolute magnitudes and slope parameters for 250,000 asteroids observed by Pan-STARRS PS1 - Preliminary results". Icarus. 261: 34–47. arXiv:1506.00762. Bibcode:2015Icar..261...34V. doi:10.1016/j.icarus.2015.08.007. Retrieved 30 June 2016.
- ↑ "MPC/MPO/MPS Archive". Minor Planet Center. Retrieved 30 June 2016.
External links
- Asteroid Lightcurve Database (LCDB), query form (info)
- Dictionary of Minor Planet Names, Google books
- Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
- Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
- 4902 Thessandrus at the JPL Small-Body Database