NASA scientists have analyzed images from the Mars Reconnaissance Orbiter to realize that a prehistoric lake on the Red Planet’s surface may hold the best possible odds of finding evidence of life. According to a report from The Examiner, scientists estimate that the lake formed long after life had flourished here on Earth.

The photos come from a region on Mars that is just about 100 miles from the current location of NASA’s Opportunity rover. Scientists believe that Mars was full of water billions of years ago, and a large lake was created in the photographed region. Channels dug into the rocky surface offer a glimpse into how the water traveled throughout the region, and geologists suspect that this is the best possible spot to search for evidence of life.

The channels also offer insight into the lakebed’s age. They run towards a series of volcanic plains hundreds of miles away, near Mars’ equator. The plains are estimated to be about 3.6 billion years old, so the channels must have formed sometime after then.

Researchers are especially interested in the salt deposits in the lake’s bed. According to head researcher Brian Hynek, organic matter is deposited in the sediments at the bottom of bodies of water, and any evidence of microbial life would have been preserved in the salts. If there were microscopic organisms living in the lake billions of years ago, there is a high chance that the salt deposits would have kept them intact.

NASA will send the next rover to Mars in 2020, and scientists hope to further explore the mysteries of the newly-discovered lake on the Red Planet.