Mars trojan

The L₅ group (shown in green) and the L₄ group (light blue) of Mars trojans on the orbit of Mars. Mars is shown in red. The outer orbit is that of Jupiter.

The Mars trojans are a group of objects that share the orbit of the planet Mars around the Sun. They can be found around the two Lagrangian points 60° ahead of and behind Mars. The origin of the Mars trojans is not well understood. One theory suggests that they were captured in its Lagrangian points as the Solar System was forming. However, spectral studies of the Mars trojans indicate this may not be the case.^[1][2] One explanation for this involves asteroids wandering into the Mars Lagrangian points later in the Solar System's formation. This is also questionable considering the very low mass of Mars.^[3][4]

Presently, this group contains seven asteroids confirmed to be stable Mars trojans by long-term numerical simulations but only four of them are accepted by the Minor Planet Center (†)^[5] and there is one candidate:^[3][4][6][7]

L₄ (leading):

• (121514) 1999 UJ7 †

L₅ (trailing):

• 5261 Eureka †
• (101429) 1998 VF31 †
• (311999) 2007 NS2 †
• (385250) 2001 DH47
• 2011 SC191
• 2011 UN63

Candidates

• 2011 SL25

See also

• Trojan (astronomy)
• Minor planets that orbit near trojan points
  • Earth trojan
  • Jupiter trojan
  • Neptune trojan

References

1. Rivkin, Andrew; Trilling, David; Thomas, Cristina; DeMeo, Fancesca; Spahr, Timoth; Binzel, Richard (2007). "Composition of the L5 Mars Trojans: Neighbors, not siblings". Icarus 192 (2): 434–441. arXiv:0709.1925. Bibcode:2007Icar..192..434R. doi:10.1016/j.icarus.2007.06.026.
2. Trilling, David; Rivking, Andrew; Stansberry, John; Spahr, Timothy; Crudo, Richard; Davies, John (2007). "Albedos and diameters of three Mars Trojan asteroids". Icarus 192 (2): 442–447. arXiv:0709.1921. Bibcode:2007Icar..192..442T. doi:10.1016/j.icarus.2007.08.002.
3. Scholl, H.; Marzari, F.; Tricarico, P. (2005). "Dynamics of Mars Trojans". Icarus 175 (2): 397–408. Bibcode:2005Icar..175..397S. doi:10.1016/j.icarus.2005.01.018.
4. Schwarz, R.; Dvorak, R. (2012). "Trojan capture by terrestrial planets". Celestial Mechanics and Dynamical Astronomy 113 (1): 23–34. Bibcode:2012CeMDA.113...23S. doi:10.1007/s10569-012-9404-4.
5. "List Of Martian Trojans". Minor Planet Center. Retrieved 2013-03-04.
6. de la Fuente Marcos, Carlos; de la Fuente Marcos, Raúl (April 2013). "Three new stable L5 Mars Trojans". Monthly Notices of the Royal Astronomical Society: Letters 432 (1): L31–L35. arXiv:1303.0124. Bibcode:2013MNRAS.432L..31D. doi:10.1093/mnrasl/slt028.
7. Christou, A. A. (2013). "Orbital clustering of Martian Trojans: An asteroid family in the inner solar system?". Icarus 224 (1): 144–153. arXiv:1303.0420. Bibcode:2013Icar..224..144C. doi:10.1016/j.icarus.2013.02.013.