2011 SL25, also written as 2011 SL25, is an asteroid and Mars trojan candidate that shares the orbit of the planet Mars at its L5 point.[2]
Discovery, orbit and physical properties
2011 SL25 was discovered on 21 September 2011 at the Alianza S4 Observatory (I08) on Cerro Burek in Argentina[3] and classified as Mars-crosser by the Minor Planet Center. It follows a relatively eccentric orbit (0.11) with a semi-major axis of 1.52 AU.[3] This object has noticeable orbital inclination (21.5°).[3] Its orbit was initially poorly constrained, with only 76 observations over 42 days, but was recovered in January 2014.[1]2011 SL25 has an absolute magnitude of 19.5 which gives a characteristic diameter of 575 m.[1]
Mars trojan and orbital evolution
Recent calculations indicate that it is a stable L5 Mars Trojan with a libration
period of 1400 yr and an amplitude of 18°.[2][4] values as well as its short-term orbital evolution are similar to those of 5261 Eureka.[5][6]
Origin
Long-term numerical integrations show that its orbit is stable on Gyr time-scales (1 Gyr = 1 billion years). It appears to be stable at least for 4.5 Gyr but its current orbit indicates that it has not been a dynamical companion to Mars for the entire history of the Solar System.[2]
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.