2011 QF99
Discovery | |
---|---|
Discovery date | 2011[1] |
Designations | |
centaur | |
Orbital characteristics[1][2] | |
Epoch 13 January 2016 (JD 2457400.5) | |
Uncertainty parameter 3 | |
Observation arc | 1449 days (3.97 yr) |
Aphelion | 22.487 AU (3.3640 Tm) |
Perihelion | 15.676 AU (2.3451 Tm) |
19.081 AU (2.8545 Tm) | |
Eccentricity | 0.17846 |
83.35 yr (30445 d) | |
277.47° | |
0° 0m 42.57s /day | |
Inclination | 10.8233° |
222.5096° | |
287.63° | |
Earth MOID | 14.7043 AU (2.19973 Tm) |
Jupiter MOID | 10.4391 AU (1.56167 Tm) |
Physical characteristics | |
Dimensions | ~60 km[2] |
0.05 (assumed) | |
9.6 (r-band)[2] 9.7[1] | |
|
2011 QF99 is the first and, as of 2015, the only known Uranus trojan.[2][3] It was discovered in 2011 during a deep survey of trans-Neptunian objects conducted with the Canada–France–Hawaii Telescope.[2][4] It is thought to be roughly 60 km in diameter, assuming an albedo of 0.05.[2]
2011 QF99 temporarily orbits near Uranus's L4 Lagrangian point (leading Uranus). It will continue to librate around L4 for at least 70,000 years and will remain a Uranus co-orbital for up to three million years before becoming a centaur. 2011 QF99 is thus a temporary Uranus trojan—a centaur captured some time ago.[2]
Uranus trojans are generally expected to be unstable and none of them are thought to be of primordial origin. A simulation led to the conclusion that at any given time, 0.4% of the centaurs in the scattered population within 34 AU would be Uranus co-orbitals, of which 64% (0.256% of all centaurs) would be in horseshoe orbits, 10% (0.04%) would be quasi-satellites, and 26% (0.104%) would be trojans (evenly split between the L4 and L5 groups).[2]
References
- 1 2 3 "JPL Small-Body Database Browser: 2011 QF99". Retrieved 31 March 2016.
- 1 2 3 4 5 6 7 8 Alexandersen, M.; Gladman, B.; Greenstreet, S.; Kavelaars, J. J.; Petit, J. -M.; Gwyn, S. (2013). "A Uranian Trojan and the Frequency of Temporary Giant-Planet Co-Orbitals". Science. 341 (6149): 994–997. arXiv:1303.5774. Bibcode:2013Sci...341..994A. doi:10.1126/science.1238072. PMID 23990557.
- ↑ Choi, C. Q. (2013-08-29). "First 'Trojan' Asteroid Companion of Uranus Found". Space.com web site. TechMediaNetwork. Retrieved 2013-09-03.
- ↑ Alexandersen, M.; Kavelaars, J.; Petit, J.; Gladman, B. (18 March 2013). "MPEC 2013-F19: 2011 QF99". IAU. Retrieved 3 September 2013.
External links
- 2011 QF99 at the JPL Small-Body Database