A member of one of two groups of asteroids, at a mean distance of 5.2 au from the Sun, which share the orbit of Jupiter. They lie clustered around the leading (L₄) and following (L₅) Lagrangian points, 60° ahead of and behind Jupiter. Perturbations by other planets cause the Trojans to oscillate along the orbit of Jupiter about 45–80° from the planet, taking 150–200 years per cycle. The first Trojan to be discovered was Achilles in 1906 in the leading (L₄) point, followed that same year by (617) Patroclus in the trailing (L₅) position. As of 2017, over 6500 Trojan asteroids were known, 64% in the leading (L₄) group. In 1990 the first Martian Trojan, (5261) Eureka, was discovered in the L₅ region of Mars’s orbit, and the first at the L₄ point was (121514) in 1999. In 2001 the first Neptunian Trojan (2001 QR₃₂₂) was discovered at Neptune’s leading (L₄) Lagrangian point; the first Neptunian L₅ Trojan was 2008 LC₁₈ in 2008. In 2010 the first Earth Trojan, 2010 TK₇, was discovered at the leading (L₄) point; it is about 0.4 km in diameter. The first Uranus trojan, 2011 QF₉₉, was discovered in 2011 at the L₄ point of its orbit.

http://www.minorplanetcenter.net/iau/lists/Trojans.html Database of Trojan minor planets.