NASA scientists think evidence of ancient life on Mars may have been “erased”.
The US space agency’s Curiosity rover has discovered that parts of the planet’s rock record are missing and this could be due to super-salty water, also known as brine.
1
Ashwin Vasavada, a Curiosity project scientist, said: “We’ve learned something very important: There are some parts of the Martian rock record that aren’t so good at preserving evidence of the planet’s past and possible life.”
Billions of years ago, scientists think Mars was full of lakes that could have been home to microbial life.
The Red Planet’s climate is thought to have changed and dried out its lakes.
One of those lakes was at the Gale Crater, which Nasa’s Curiosity rover has been studying.
A new study suggests that as the lake dried, salty brines seeped into clay and mineral layers at the bottom of the lake and altered them.
“Brines broke down these clay minerals in some places”
Tom Bristow, CheMin principal investigator, said: “We used to think that once these layers of clay minerals formed at the bottom of the lake in Gale Crater, they stayed that way, preserving the moment in time they formed for billions of years.
“But later brines broke down these clay minerals in some places – essentially resetting the rock record.”
The scientists targeted the Gale Crater because they thought its undisturbed layers of ancient rocks could teach us about Mars’s history and possible life.
Similar samples collected from other areas of Mars where compared to those from the Gale Crater and researchers were shocked to find that around half the clay minerals they were expecting to find were missing.
Minerals can act like time capsules by providing scientists with a record of what the planet was like when they formed.
Clay minerals contain water in their structure and are used as evidence that the sediments they’re found in came into contact with water.
Liz Rampe, CheMin deputy principal investigator and co-author at NASA’s Johnson Space Center, said: “Since the minerals we find on Mars also form in some locations on Earth, we can use what we know about how they form on Earth to tell us about how salty or acidic the waters on ancient Mars were.”
The researchers will continue their investigation into Mars’s rocks and what they can tell us.
A study about the brine theory has been published in the journal Science.
NASA shows off their Ingenuity Mars Helicopter in action
In other news, Jeff Bezos says his Blue Origin mission was a ‘tiny step in building a road to space’.
Sir Richard Branson made history earlier this month after successfully reaching space in his commercial Virgin Galactic spaceplane.
And, aliens may have dropped life-detecting sensors onto Earth, according to a Harvard University professor.
We pay for your stories! Do you have a story for The Sun Online Tech & Science team? Email us at [email protected]
This post first appeared on Thesun.co.uk
