Los Alamos National Laboratory

Los Alamos National Laboratory

Delivering science and technology to protect our nation and promote world stability

Did life sign the guestbook on Mars?

If life exists on Mars, it still hasn’t showed itself, but recent evidence from the red planet increasingly supports the possibility
July 18, 2019
Curiosity rover

.

Did life sign the guestbook on mars?

by Nina Lanza and Chris Yeager

If life exists on Mars, it still hasn’t showed itself, but recent evidence from the red planet increasingly supports the possibility. Life could have developed there. Most of the conditions are right and nothing found so far rules out the possibility, either in the distant past or today.

If something is or was alive there, it’s probably tiny. Since microbes make up the vast majority of life on Earth and live in its most inhospitable environments, microbes are the most likely thing to find somewhere else. It’s not so easy figuring out what “alive” means on another planet—let alone finding a living microbe. Scientists are still puzzled by life on Earth. We are struggling to understand how life started, what it requires to survive, what it looked like 4 billion years ago, and how to recognize traces of ancient life today.

Solving these mysteries demands the latest and best laboratory tools and lots of samples from the field—two things that are hard to come by on a planet 34 million miles away from Earth. So it doesn’t mean much that we have not yet seen life on Mars.

This story first appeared in Scientific American.