Trojan asteroid

A trojan asteroid is an asteroid orbiting in the 4th or 5th Lagrange point of a major planet in the Solar System. Currently there are six planets known to have trojans:

It is possible Mercury and Saturn have trojan asteroids, but none have been discovered so far due to Mercury's proximity to the Sun hindering the observation of such objects, and Saturn's proximity to Jupiter throwing possible would-be trojans out of a stable orbit with Saturn.

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