As you know, the red color of Mars is because of the Iron oxide on it, why there is Iron oxide?
Iron is one of the most abundant elements in the universe so there is iron everywhere. It would be more stange if there were none on Mars. What is interesting about your question why there is ironoxide on Mars. Why Mars is red. This type of iron oxide is usually associated with water and oxygen suggesting Mars once had water flowing on it.
The vast amount of meteor impacts with no erosion, leaves a lot of iron on the surface.
