"they were once in contact with lots of water."
Yea so....carbon date the bitches already! WE WANNA KNOW IF THE DAMN ALIENS ARE THERE! heh, for real, they need to move on that, life in any form usually exists around water or ice. If there are underground storages of unfrozen water that would change all understandings currently of mars.
"Beware the Jabberwock, my son!
The jaws that bite, the claws that catch!
Beware the Jubjub bird, and shun
The frumious Bandersnatch!"