"Our work is a new piece of evidence that suggests that Mars was once a much more complex and active planet than it is now."

If aliens existed on Mars 3.7 billion years ago, they would have needed umbrellas

Source: space
Source Link: https://www.space.com/astronomy/mars/if-aliens-existed-on-mars-3-7-billion-years-ago-they-would-have-needed-umbrellas