Mars: clues to ancient water
Mars is a rocky planet with dusty, reddish ground. Its color comes from iron minerals that have reacted with oxygen.
Rovers study rocks and landscapes for clues about the past. Some clues show that liquid water once flowed there.
Wonder about this
Do signs of an ancient Martian lake prove there were Martian animals?
A science clue
No. They show past water and a potentially interesting environment, not confirmed life.