Up there, within our own Solar system (and beyond) everything is in motion. There is no space object that is standing still. Ever since the big bang. Even the black holes that are capturing things into singularity point are moving across the universe along with their own neighborhood. The same is with Earth and its first neighbor Mars. They are both orbiting the Sun in their own time schedule - Earth needs full year to complete the cycle, while Mars in its own distant orbit needs 322 more days to do it. While both, Earth and Mars travel around the Sun, sometimes they got closer to each other by the approximate 55 million kilometers (while the farthest distance between the two is about 400 million kilometers).