2011 UN63

Mars trojan asteroid February 2018 yes #FA8072 2011 UN 63 Mt. Lemmon Survey 21 October 2011 2011 UN 63 Martian L5 125 13 January 2016 (JD 2457400.5) 1.6222522 AU Gm on on 1.4253677 AU Gm on 1.5238099 AU Gm on 0.0646027 1.88 yr (687.06 d) 20.36086° 223.55542° 101.29418° 165.28918° 560 m 0.5–0.05 (assumed) 19.7 0.5239717 ms / day 1587 days (4.34 yr) 1 0.434823 AU Gm on 3.54877 AU Gm on 2011 UN 63 is a Mars trojan, an asteroid orbiting near the yes of Mars (60 degrees behind Mars on its orbit).Three new stable L5 Mars Trojans C. de la Fuente Marcos de la Fuente Marcos R. April 2013 Monthly Notices of the Royal Astronomical Society: Letters 432 1 L31–L35 10.1093/mnrasl/slt028 free 1303.0124 2013MNRAS.432L..31D Discovery, orbit and physical properties 2011 UN 63 was first observed on 27 September 2009 by the Mt. Lemmon Survey and given the provisional designation 2009 SA 170. Lost, it was re-discovered on 21 October 2011 again by the Mt. Lemmon Survey. 2011 UN 63 follows a low eccentricity orbit (0.064) with a semi-major axis of 1.52 AU.MPC data on 2011 UN63 This object has moderate orbital inclination (20.4°). It was classified as Mars-crosser by the Minor Planet Center upon discovery. Its orbit is relatively well determined as it is currently (March 2013) based on 64 observations with a data-arc span of 793 days.http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=2011UN63;cad=1 JPL Small-Body Database Browser: (2011 UN63) Jet Propulsion Laboratory 31 March 2016 This asteroid has an absolute magnitude of 19.7 which gives a characteristic diameter of 560 m. Mars trojan and orbital evolution Recent calculationsChristou, A. A. Orbital clustering of Martian Trojans: An asteroid family in the inner solar system? Icarus 224 1 144–153 2013 10.1016/j.icarus.2013.02.013 2013Icar..224..144C 1303.0420 119186791 indicate that it is a stable Mars trojan asteroid with a libration period of 1350 yr and an amplitude of 14°. These values as well as its short-term orbital evolution are similar to those of 5261 Eureka or 2011 SC 191. Origin Long-term numerical integrations show that its orbit is very stable on Gyr time-scales (1 Gyr = 1 billion years). As in the case of Eureka, calculations in both directions of time (4.5 Gyr into the past and 4.5 Gyr into the future) indicate that 2011 UN 63 may be a primordial object, perhaps a survivor of the planetesimal population that formed in the terrestrial planets region early in the history of the Solar System. See also 5261 Eureka (1990 MB) (101429) 1998 VF 31 (121514) 1999 UJ 7 (311999) 2007 NS 2 (385250) 2001 DH 47 (816688) 2011 SC 191 2009 SE 2011 SL 25 2011 SP 189 2011 UB 256 2016 CP 31 2018 EC 4 2018 FC 4 2020 VT 1 References Further reading Three new stable L5 Mars Trojans de la Fuente Marcos, C., de la Fuente Marcos, R. 2013, Monthly Notices of the Royal Astronomical Society: Letters, Vol. 432, Issue 1, pp. 31–35. Orbital clustering of Martian Trojans: An asteroid family in the inner solar system? Christou, A. A. 2013, Icarus, Vol. 224, Issue 1, pp. 144–153. External links 2011 UN 63 data at MPC 2011 UN 63 data at AstDyS-2. 3469622 Solar System Category:Mars trojans * Category:Minor planet object articles (unnumbered) 20090927 20111021