The Trojan Asteroids are groups of asteroids that share orbits with planets, clustered at the L4 and L5 Lagrangian points—stable gravitational zones 60 degrees ahead and behind a planet. The largest population orbits with Jupiter, divided into Greek (L4) and Trojan (L5) camps, extending from about 5 AU.
Smaller Trojan groups exist with Mars, Neptune, Earth, and Uranus.
Named after characters from the Trojan War in Greek mythology, with the first Jupiter Trojan, Achilles, discovered in 1906 by Max Wolf.
Key events include NASA's Lucy mission launch in 2021 to explore seven Jupiter Trojans, aiming for flybys starting in 2027, and Hubble observations of active Trojans like 2019 LD2 showing comet-like activity. These primordial remnants offer clues to the solar system's early composition and planetary formation.
