New surprises from Mars: Volcanic rock, more signs of water in the past

Samples drilled by NASA's Perseverance rover from a crater on Mars are revealing signs that the cold arid planet may have been once warm and wet.

The rock collected from four sites inside the Jezero crater on the Martian surface also turned out to be igneous - formed by the cooling of molten material like magma - and not sedimentary.

If you are wondering whether all this sounds a bit like Earth in its earlier days, here is what scientists have to say: The rocks bore evidence of alteration through exposure to water


The area containing the Jezero crater is just north of the Martian equator, and it appears the area once was abundant with water and home to a river delta.

The water may have spilled over to collect inside the crater as a lake, and scientists suspect - there is no evidence yet - that its bed may have once harboured life in an early form.

"I came to the ancient lakebed of Jezero Crater expecting lots of sedimentary rocks. I see them now at the old river delta, but the crater floor was a surprise: lots of volcanic rocks, said a tweet from NASA's Perseverance team on Friday.

That there were no sediments found despite the likely presence of water in the area in the far past has led scientists to suspect it may have been washed away.

These info are contained in four studies on Martian geology published in the journals Science and Science Advances.

Perseverance rover, which arrived on Mars in February 2021, is gathering rock samples in small tubes. They will be collected by a spacecraft in 2033 to be brought to Earth for further examination.

Scientists will be studying those samples closely for biosignatures - indicators that life in some form may have once existed on our neighbouring planet.