Trajectory analysis for combined missions to mars and its Trojan Asteroids

Abstract

While standalone missions to the Trojan Asteroids of Mars are costly, we analyze flyby scenarios of Mars Trojans, which can be achieved in combination with missions to Mars. We find several trajectory options within the time window 2025–2050, which allow flybys at seven of the known Trojan asteroids located at L5 (trailing by approximately 60° behind Mars) with a low demand for additional delta-v of 0.02–1 ​km/s compared to a nominal Mars mission. On the other hand, the minimal cruise duration from Earth to the Trojan and from the Trojan to Mars adds up to at least 2 years as more than one revolution about the sun is required for the spacecraft. For the unique L4 Trojan no practical trajectory solution was found. All Trojans have a significant inclination of more than 10° relative to the orbital plane of Mars, which implies high flyby velocities (v ​= ​6–13 ​km/s) for spacecraft approaching from within this plane.