21900 Orus

21900 Orus
Discovery [1]
Discovered by T. Kobayashi
Discovery site Ōizumi Obs.
Discovery date 9 November 1999
Designations
MPC designation 21900 Orus
Pronunciation /ˈɔərəs/
Named after
 Orus (Greek mythology)[2]
1999 VQ10 · 1998 VD18
Jupiter trojan [1][3]
Orbital characteristics [1]
Epoch 13 January 2016 (JD 2457400.5)
Uncertainty parameter 0
Observation arc 64.27 yr (23,474 days)   
Aphelion 5.3111 AU
Perihelion 4.9453 AU
5.1282 AU
Eccentricity 0.0356
11.61 yr (4,242 days)
135.06°
Inclination 8.4658°
258.56°
181.22°
Physical characteristics
Dimensions 53.87±4.08 km[4]
50.81±0.81 km[5]
55.67 km (calculated)[3]
13.45±0.08 h[6]
0.083±0.015[4]
0.075±0.014[5]
0.057 (assumed)[3]
C [3][7]
10.0[1][3]
9.80[4]
9.9[5]
10.12±0.32[7]

    21900 Orus, provisional designation 1999 VQ10, is a carbonaceous Jupiter trojan, about 53 kilometers in diameter. It was discovered by Japanese amateur astronomer Takao Kobayashi at his private Ōizumi Observatory in Gunma Prefecture, Japan, on 9 November 1999.[2] It may be visited by the spacecraft Lucy, a proposed mission concept by NASA as of 2016.[8]

    The dark C-type body orbits the Sun in Jupiter's leading L4 point at a distance of 4.9–5.3 AU once every 11 years and 7 months (4,242 days). Its orbit shows an eccentricity of 0.04 and an inclination of 8 degrees from the plane of the ecliptic.[1] In 2009, the body was observed in a photometric light-curve survey of 80 Jupiter trojans, which rendered a rotation period of 13.45±0.08 hours with a brightness amplitude of 0.18 in magnitude (Q=2).[6]

    According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, the body has an albedo of 0.083 and 0.075, with a diameter of 53.9 and 50.8 kilometers, respectively.[4][5] The Collaborative Asteroid Lightcurve Link (CALL) assumes a lower albedo of 0.057 and calculates a diameter of 55.7 kilometers.[3]

    The minor planet was named from Greek mythology after Orus, an Achaean warrior in Homer's Iliad. He was killed in the Trojan war by the Trojan prince Hector,[2] after whom the largest Jupiter trojan, 624 Hektor, is named.

    See also

    References

    1. 1 2 3 4 5 "JPL Small-Body Database Browser: 21900 Orus (1999 VQ10)" (2016-02-14 last obs.). Jet Propulsion Laboratory. Retrieved March 2016.
    2. 1 2 3 "21900 Orus (1999 VQ10)". Minor Planet Center. Retrieved March 2016.
    3. 1 2 3 4 5 6 "LCDB Data for (21900) Orus". Asteroid Lightcurve Database (LCDB). Retrieved February 2016.
    4. 1 2 3 4 Usui, Fumihiko; Kuroda, Daisuke; Müller, Thomas G.; Hasegawa, Sunao; Ishiguro, Masateru; Ootsubo, Takafumi; et al. (October 2011). "Asteroid Catalog Using Akari: AKARI/IRC Mid-Infrared Asteroid Survey". Publications of the Astronomical Society of Japan 63 (5): 1117–1138. Bibcode:2011PASJ...63.1117U. doi:10.1093/pasj/63.5.1117. Retrieved February 2016.
    5. 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". The Astrophysical Journal 741 (2): 25. arXiv:1109.6407. Bibcode:2011ApJ...741...90M. doi:10.1088/0004-637X/741/2/90. Retrieved February 2016.
    6. 1 2 Mottola, Stefano; Di Martino, Mario; Erikson, Anders; Gonano-Beurer, Maria; Carbognani, Albino; Carsenty, Uri; et al. (May 2011). "Rotational Properties of Jupiter Trojans. I. Light Curves of 80 Objects". The Astronomical Journal 141 (5): 32. Bibcode:2011AJ....141..170M. doi:10.1088/0004-6256/141/5/170. Retrieved February 2016.
    7. 1 2 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 February 2016.
    8. ↑ Casey Dreier; Emily Lakdawalla (30 September 2015). "NASA announces five Discovery proposals selected for further study". The Planetary Society. Retrieved February 2016.

    External links

    This article is issued from Wikipedia - version of the Sunday, April 17, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.