Two moons and five spacecraft: it’s getting pretty crowded up there. So how do all those Martian satellites manage to keep missing each other?

NASA put together this map of what all is drifting around up there, and it has us wondering just how they all manage to keep missing each other. Essentially, there are two things responsible for keeping all those moons and spacecraft intact.


The first is that the orbits that the different spacecraft are traveling in are not all the same. Maven, for instance, circles up much higher than the other spacecraft orbiting Mars. That still, however, leaves a number of craft in the same orbit — not to mention Phobos and Deimos, Mars’ two tiny, sort of lumpy moons, both of which have orbits that cross paths with the spacecrafts.

Which is why a second scenario is also necessary, what NASA calls “a collision-avoidance maneuver.” Scientists for each mission keep close track of the anticipated orbits not just for their own mission, but also for the others. And, when they get a little too close for comfort, they can make a plan with the other mission team to preemptively stop any space crashes.

Image: NASA/JPL-Caltech