Satellite observations of the Jezero Crater on Mars which was selected as a landing pad for [NASA's next rover mission have yielded clues to minerals that are exceptionally good at leaving traces of ancient life to preserve what it balances Better place to send the rover than originally thought.
If there were still primitive lives on Mars billions of years ago – and that's still a big problem – there's a terrific chance that the fossil remains of this life will be found in zero craters after a couple of recent studies. This is an exceptionally good news, since the yet to be named NASA Rover 2020 will be launched at this exact location next year.
That the Jezero Crater is an outstanding target for the Rover is no surprise since it was carefully selected by NASA for its potentially life-friendly qualities or at least its . former potentially life-friendly features. Billions of years ago, this 49-kilometer-wide (30 ̵
In a work published in Geophysical Letters a research team led by Brown University PhD. student Jesse Tarnas describes the discovery of hydrated silicic acid in rock ledges on the edge of an ancient river delta. This is big news as hydrated silica, a form of silica, is known to preserve fossilized evidence of ancient life on earth.
And in a separate publication published in Icarus, a research team headed by Briony Horgan of Purdue University describes the presence of carbonates in the Jezero Crater, a mineral that also traces very well can preserve ancient life and other important biosignatures.
Both discoveries were made possible by the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) located on NASA's Mars Reconnaissance Orbiter (MRO). Since hydrated silica provides weak spectral signals, Tarnas and his colleagues were able to confirm the signatures using two Big Data processing techniques. To find the carbonates, Horgan and her team used the CRISM data in conjunction with high-resolution images and topographic models of the Martian surface.
Tarnas and his colleagues did not necessarily expect to find evidence of hydrated silica .
"We started the project with a new data analysis method that we developed for hyperspectral images to transfer composition information about the Martian surface from orbit to images of the Jezero Crater and the surrounding region," Tarnas wrote after Gizmodo in an E -Mail. "When we started, the Jezero Crater was not yet selected as the landing pad for the NASA Mars 2020 rover. Therefore, we were interested in finding new minerals or mineral deposits both inside and outside of Jezero, as NE Syrtis, another final landing site candidate. was very close.
When the ancient rivers flowed into the crater, they transported minerals from the watershed and created a fan-delta deposit that is now rich in clay materials. As described in the publication Geophysical Letters, at the edge of this delta at low altitude is a hydrated silicic acid deposit. This suggests that minerals have formed at the bottom of the delta, known as the bottom-set layer, making it an ideal site for the 2020 rover.
"These minerals and mineral deposits provide information about the conditions under which water and rock interacted in this Martian region," Tarnas said. "Most of this water-rock interaction took place billions of years ago. Some of these chemical reactions between water and rocks create habitable environments, including the probable habitable environment of the ancient lake of the Jezero Crater, which has been formed by physical movement of water over rocks. "
Heavy signatures of carbonates have been detected on the western edge of Jezero's crater, which Horgan described in a NASA press release as a" bathtub ring ". Carbonates typically form in shallow and warm seas and often in conjunction with biological activity, hence the interest in carbonates on Mars. On Earth, Carbona contributes to the fossilization of structures such as shells, corals and, above all, stromatolites – rocky structures formed by large lumps of microbial life. Granted, traces of shells and corals on Mars are highly unlikely, but evidence of bacteria-like microorganisms, well, that's another story.
Regarding what this preserved Martian life might look like, Tarnas said it "would probably look like microbial cells that are permineralized in the hydrated silica, meaning that silica grows in the interstices between the cell walls and the rock that contains the microfossils, probably rich in complex organic matter. "He said it may resemble the ancient microfossils found in silica from ancient rocks, including 3.4 billion year old fossils found in South Africa and Australia.
Interestingly, both the hydrated silicic acid and the carbonates should be readily accessible with the 2020 Rover on the Martian surface. The Rover has a built-in chemical laboratory for testing samples and an instrument for detecting complex organic compounds. The rover can also take close-up views of the deposits to see how they are positioned relative to other rocks. It also has CRISM-like sensors that allow comparative analysis with MRO data. Otherwise, the rover can extract samples and use them as a cache for future missions to retrieve and return to Earth for analysis.
This is all very exciting, and we do not want to mention the news from the beginning of this week about the discovery of fascinating oxygen fluctuations on Mars. There may have been a lifetime on the Red Planet, but we'll do our best to find out. The good news is that we will not have to wait long for the new rover to snoop around in the Jezero Crater – February 2021 will surely arrive in a moment.