Martian L5 asteroid
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 primordial objects leftover 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. 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. The spectra of Eureka and two other Mars Trojan indicates an olivine-rich composition. Since olivine-rich objects are rare in the asteroid belt it has been suggested that some of the Mars trojans are debris from a large impact on Mars that was captured when the orbit of Mars was altered when it encountered encountered a planetary embryo.
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 (†) and there is one candidate:
L4 (leading):
L5 (trailing):
Candidates
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