Martian Trojan asteroids have stable orbits around the Sun, leading and trailing the red planet by 60 degrees, where the Sun's and Mars's gravity are balanced. The impact more than 4 billion years or so ago which blasted loose the Trojan asteroids and gave them the 3mi/s required to escape the red planet gives us an insight into the level of violence which occurred before our solar system came into it's present relatively calm state.
