A meteorite find in the US in the 1930s has been under the microscope – see http://phys.org/print301725844.html. Research has shown the meteorite, or space rock, had an origin on Mars – and it landed on Earth around 3000 years ago (roughly at the end of the Bronze Age).
The research, in Nature Communications, suggests the atmosphere of Mars may not have escaped into space (assuming Mars did have a thicker atmosphere than it has now). Some of it, possibly lots of it, may actually be locked into the surface rocks of Mars. This revolves around the idea that Mars once had a carbon rich atmosphere – which was lost (billions of years ago). Why is was lost is a mystery – of course. The researchers are suggesting it was sucked into the ground on Mars – which is different to the other explanations so far aired.
The meteorite from Mars, I must emphasize ebfore anybody gets ideas otherwise, was not blasted off Mars 3000 years ago – that is when it ended up on Earth's surface, presumably as a meteorite, or a fragment of a larger space rock that broke up in the atmosphere. The rock that was ejected from Mars, after an explosion of some kind, possibly an impact event – but assumed by the researchers to be volcanic in origin, occurred as long ago as 1.3 billion years ago (I don't know on what basis the dates are calculated). In other words, the meteorite was orbiting around in space for over a billion years before it landed on the Earth. The research is claiming that something happened to the makeup of the rock between the time it was formed 3 billion years ago and the date when it was blasted into space 1.3 billion years ago. They are not concerned with what happened to the space rock after the latter date – only that it landed on Earth. That involved carbonisation – the process to which minerals absorb carbon dioxide in the presence of water. Carbonisation is commonplace in earthly contexts and it si part of current thinking that significant quantities of co2 from the atmosphere end up stored over geological timescales. These are perhaps articles of faith that have been adopted to uniformitarian models.
So, the paper is really transferring modern CAGW theory to Mars, claiming they have found evidence of co2 sequestraton and storage in rocks. It is an interesting line of enquiry but I was intrigued by the date when the rock landed on Earth – was it one fragment of a much larger rock, a sort of giant Russian meteor that was involved in the end of LB age events, exploding in the atmosphere and disintegrating (with pieces of space rock ending up in diverse locations). Conversely, was it a rock in resonant orbit with another space rock, somewhat larger, and this blew up over the Agaean/Anatolia region, explaining the fire and destruction and the reference to the Star of Anat in Egyptian records. Entirely conjecture of course.