The researchers at Brown University in the US have discovered a previously unknown type of ancient crater lake on Mars that could reveal clues about the planet's early climate.
According to the study published in the Planetary Science Journal, the crater, which is yet unnamed, has eccentric characteristics and unmistakable geologic evidence of ancient stream beds and ponds.
Interestingly, no evidence of inlet channels where water could have entered the crater from outside and no evidence of groundwater activity where it could have bubbled up from below have been found.
The researchers have concluded that this water source was likely fed by runoff from a long-lost Martian Glacier. Water flowed into the crater atop the glacier and eventually emptied into the low-lying crater floor, leaving a geological mark on the bare Martian soil.
"Water flowed into the crater atop the glacier, which meant it didn't leave behind a valley as it would have had it flowed directly on the ground. The water eventually emptied into the low-lying crater floor, where it left its geological mark on the bare Martian soil," said the study.
Unlike the craters which are currently being explored by Nasa rovers like Curiosity and Perseverance, the lake described in the study is completely different and was described in the study as "a previously unrecognized type of hydrological system on Mars".
Ben Boatwright, who led the research team, said, "In lake systems characterized so far, we see evidence of drainage coming from outside the crater, breaching the crater wall and in some cases flowing out the other side. But that's not what is happening here. Everything is happening inside the crater, and that's very different than what's been characterized before."
The crater also provided key clues regarding the early climate of the red planet as there are already many speculations if the Martian climate was once warmer and wetter than the frozen desert the planet is today.
"We have these models telling us that early Mars would have been cold and icy, and now we have some really compelling geological evidence to go with it. Not only that, but this crater provides the criteria we need to start looking for even more evidence to test this hypothesis, which is really exciting," said Jim Head, a research professor at Brown.