If the world is feeling a little overwhelming this week, close your eyes for a moment. Imagine standing on a beach, your toes buried in fine red sand while a gentle breeze blows past you, bringing with it the sound of lapping water. Looking up, you can see earth, just a tiny gleaming dot above the horizon.

That’s right, this peaceful beachy scene isn’t on Earth at all, it’s on Mars! This past week, scientists have shared a Mars-shattering discovery — not only was there probably some liquid water on the red planet long long ago, there were actual lakes! This discovery is based on photographs of ripples on Mar’s surface snapped by the NASA Curiosity rover back in 2022. After extensive research, the scientific team has concluded that these ripples could only have been formed by a standing body of water that was not frozen and was being blown by the wind. Based on the size of the ripples, the team thinks they were formed by a shallow lake, maybe only 2 meters (or about 6.5 feet) deep. 

The other special thing about this lake: it was forming ripples around 3.7 billion years ago, during a time when we thought Mars was already very dry and deserty. Extending the time we think liquid water could exist on the surface also increases the likelihood of life, like microorganisms, being able to thrive on the planet’s surface. 

Personally, I like to picture little Martian crabs scuttling along the edge of this little lake, though I think this is just in my imagination. What do you think might have been swimming on Mars billions of years ago?

Want to learn more? Visit https://lindecenter.caltech.edu/news/signatures-of-ice-free-ancient-ponds-and-lakes-found-on-mars

January 26, 2025