Life on Mars? 'Leopard-spot' rocks could be biggest clue yet
The mudstones, found in a dusty riverbed by Nasa's Perseverance Rover, are dotted with intriguing markings nicknamed leopard spots and poppy seeds.
Scientists believe these features contain minerals produced by chemical reactions that could be associated with ancient Martian microbes.
![[Image: a51e1210-8e4e-11f0-b391-6936825093bd.png.webp]](https://ichef.bbci.co.uk/news/800/cpsprodpb/12ad/live/a51e1210-8e4e-11f0-b391-6936825093bd.png.webp)
"We think what we've found is evidence for a set of chemical reactions that took place in the mud that was deposited at the bottom of a lake - and those chemical reactions seem to have taken place between the mud itself and organic matter - and those two ingredients reacted to form new minerals," explained Dr Hurowitz.
In similar conditions on Earth, chemical reactions creating minerals are typically driven by microbes.
"That is one of the possible explanations for how these features came to be in these rocks," said Dr Hurowitz. "This feels like the most compelling potential biosignature detection that we've had to date."
The scientists have also examined how the minerals could have formed without microbes - and concluded that natural geological processes could also be behind the chemical reactions.
However they would require high temperatures, and the rocks don't look like they've been heated.
"We found some difficulties for the non-biological pathways - but we can't rule them out completely," Dr Hurowitz said.
https://www.bbc.com/news/articles/cd725pj0g9ro
The mudstones, found in a dusty riverbed by Nasa's Perseverance Rover, are dotted with intriguing markings nicknamed leopard spots and poppy seeds.
Scientists believe these features contain minerals produced by chemical reactions that could be associated with ancient Martian microbes.
"We think what we've found is evidence for a set of chemical reactions that took place in the mud that was deposited at the bottom of a lake - and those chemical reactions seem to have taken place between the mud itself and organic matter - and those two ingredients reacted to form new minerals," explained Dr Hurowitz.
In similar conditions on Earth, chemical reactions creating minerals are typically driven by microbes.
"That is one of the possible explanations for how these features came to be in these rocks," said Dr Hurowitz. "This feels like the most compelling potential biosignature detection that we've had to date."
The scientists have also examined how the minerals could have formed without microbes - and concluded that natural geological processes could also be behind the chemical reactions.
However they would require high temperatures, and the rocks don't look like they've been heated.
"We found some difficulties for the non-biological pathways - but we can't rule them out completely," Dr Hurowitz said.
https://www.bbc.com/news/articles/cd725pj0g9ro
teachings of the Bible are so muddled and self-contradictory that it was possible for Christians to happily burn heretics alive for five long centuries. It was even possible for the most venerated patriarchs of the Church, like St. Augustine and St. Thomas Aquinas, to conclude that heretics should be tortured (Augustine) or killed outright (Aquinas). Martin Luther and John Calvin advocated the wholesale murder of heretics, apostates, Jews, and witches. - Sam Harris, "Letter To A Christian Nation"
