Mars trojan

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The L5 group (shown in green) and the L4 group (light blue) of Mars and Jupiter Trojan asteroids shown along with the orbits of Jupiter and the inner planets. Mars is shown in red. The outer orbit is that of Jupiter. Minor Planets - Martian L5.svg
The L5 group (shown in green) and the L4 group (light blue) of Mars and Jupiter Trojan asteroids shown along with the orbits of Jupiter and the inner planets. Mars is shown in red. The outer orbit is that of Jupiter.
Animation of 1999 UJ7 relative to Sun and Mars 1600-2500

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1999 UJ7 *
Mars Animation of 1999 UJ7 relative to Sun and Mars 1600-2500.gif
Animation of 1999 UJ7 relative to Sun and Mars 1600-2500
   Sun ·  1999 UJ7 ·  Mars
Animation of 2007 NS2 relative to Sun and Mars 1600-2500

Sun *
2007 NS2 *
Mars Animation of 2007 NS2 relative to Sun and Mars 1600-2500.gif
Animation of 2007 NS2 relative to Sun and Mars 1600-2500
   Sun ·  2007 NS2 ·  Mars

The Mars trojans are a group of Trojan 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 primordial objects left over from the formation of Mars that 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] Another explanation involves asteroids chaotically wandering into the Mars Lagrangian points later in the Solar System's formation. This is also questionable considering the short dynamical lifetimes of these objects. [3] [4] The spectra of Eureka and two other Mars trojans indicates an olivine-rich composition. [5] Since olivine-rich objects are rare in the asteroid belt it has been suggested that some of the Mars trojans are captured debris from a large orbit-altering impact on Mars when it encountered a planetary embryo. [6] [3]

Presently, this group contains 14 asteroids confirmed to be stable Mars trojans by long-term numerical simulations but only nine of them are accepted by the Minor Planet Center (†). [7] [3] [4] [8] [9] [10] [11]

Due to close orbital similarities, most of the smaller members of the L5 group are hypothesized to be fragments of Eureka that were detached after it was spun up by the YORP effect (Eureka's rotational period is 2.69 h). The L4 trojan 1999 UJ7 has a much longer rotational period of ~50 h, apparently due to a chaotic rotation that prevents YORP spinup. [12]

L4 (leading):

L5 (trailing):

See also

Related Research Articles

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83982 Crantor, provisional designation 2002 GO9, is a centaur in a 1:1 resonance with Uranus, approximately 60 kilometers in diameter. It was discovered on 12 April 2002, by astronomers of the Near-Earth Asteroid Tracking at the Palomar Observatory in California, United States. This minor planet was named for Crantor from Greek mythology.

1867 Deiphobus is a dark Jupiter trojan from the Trojan camp, approximately 123 kilometers (76 mi) in diameter. It was discovered on 3 March 1971, by Argentine astronomers Carlos Cesco and A. G. Samuel at the Leoncito Astronomical Complex in Argentina, and later named after the Trojan prince Deiphobus from Greek mythology. The dark D-type asteroid is one of the largest Jupiter trojans. It is a member of the Ennomos family and has a long rotation period of 58.66 hours.

<span class="nowrap">(101429) 1998 VF<sub>31</sub></span>

(101429) 1998 VF31 is a sub-kilometer asteroid that orbits near Mars's L5 Lagrangian point, on average trailing 60° behind it. Its orbit is highly stable, and was originally thought to be spectroscopically similar to 5261 Eureka, suggesting they may both be primordial Martian asteroids.

<span class="nowrap">(311999) 2007 NS<sub>2</sub></span>

(311999) 2007 NS2 is an asteroid and Mars trojan orbiting near the L5 point of Mars.

<span class="nowrap">2011 SC<sub>191</sub></span>

2011 SC191 is a small asteroid and Mars trojan orbiting near the L5 point of Mars (60 degrees behind Mars on its orbit).

<span class="nowrap">2011 SL<sub>25</sub></span>

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.

<span class="nowrap">2011 UN<sub>63</sub></span>

2011 UN63, also written as 2011 UN63, is a Mars trojan, an asteroid orbiting near the L5 point of Mars (60 degrees behind Mars on its orbit).

2009 SE Small asteroid and Mars trojan

2009 SE is a small asteroid and Mars trojan orbiting near the L5 point of Mars (60 degrees behind Mars on its orbit).

<span class="nowrap">2018 EC<sub>4</sub></span>

2018 EC4 is a small asteroid and Mars trojan orbiting near the L5 point of Mars (60 degrees behind Mars on its orbit).

<span class="nowrap">2018 FC<sub>4</sub></span>

2018 FC4 is a small asteroid and Mars trojan orbiting near the L5 point of Mars (60 degrees behind Mars on its orbit).

<span class="nowrap">2011 SP<sub>189</sub></span>

2011 SP189 is a small asteroid and Mars trojan orbiting near the L5 point of Mars (60 degrees behind Mars on its orbit).

<span class="nowrap">2011 UB<sub>256</sub></span>

2011 UB256 is a small asteroid and Mars trojan orbiting near the L5 point of Mars (60 degrees behind Mars on its orbit).

<span class="nowrap">2016 CP<sub>31</sub></span>

2016 CP31 is a small asteroid and Mars trojan orbiting near the L5 point of Mars (60 degrees behind Mars on its orbit).

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. 1 2 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. 1 2 Schwarz, R.; Dvorak, R. (2012). "Trojan capture by terrestrial planets". Celestial Mechanics and Dynamical Astronomy. 113 (1): 23–34. arXiv: 1611.07413 . Bibcode:2012CeMDA.113...23S. doi:10.1007/s10569-012-9404-4.
  5. Borisov, G.; Christou, A.; Bagnulo, S.; Cellino, A.; Kwiatkowski, T.; Dell'Oro, A. (2017). "he olivine-dominated composition of the Eureka family of Mars Trojan asteroids". Monthly Notices of the Royal Astronomical Society. 466 (1): 489–495. arXiv: 1701.07725 . Bibcode:2017MNRAS.466..489B. doi:10.1093/mnras/stw3075.
  6. Polishook, D.; Jacobson, S. A.; Morbidelli, A.; Aharonson, O. (2017). "A Martian origin for the Mars Trojan asteroids". Nature Astronomy. 1: 0179. arXiv: 1710.00024 . Bibcode:2017NatAs...1E.179P. doi:10.1038/s41550-017-0179.
  7. "List Of Martian Trojans". Minor Planet Center. Retrieved 2021-01-12.
  8. 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.
  9. 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.
  10. Christou, Apostolos A.; Borisov, Galin; Dell'Oro, Aldo; Cellino, Alberto; Devogèle, Maxime (January 2021). "Composition and origin of L5 Trojan asteroids of Mars: Insights from spectroscopy". Icarus. 354 (1): 113994 (22 pages). arXiv: 2010.10947 . Bibcode:2021Icar..35413994C. doi:10.1016/j.icarus.2020.113994.
  11. de la Fuente Marcos, Carlos; de la Fuente Marcos, Raúl (March 2021). "Using Mars co-orbitals to estimate the importance of rotation-induced YORP break-up events in Earth co-orbital space". Monthly Notices of the Royal Astronomical Society . 501 (4): 6007–6025. arXiv: 2101.02563 . Bibcode:2021MNRAS.501.6007D. doi:10.1093/mnras/stab062.
  12. Lovett, R. (2017-10-20). "Sun's light touch explains asteroids flying in formation behind Mars". Science. doi:10.1126/science.aar2794.