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Before-and-after images from the Context Camera on NASA's Mars Reconnaissance Orbiter show a section of Mars' surface where the European Space Agency's lander is believed to have met its end.Source: NASA/JPL-Caltech/MSSS
Instead of drifting gently onto Mars' surface, the Schiaparelli Mars lander hit the planet hard — and possibly exploded. That's the word from the European Space Agency, which says new images taken by NASA show the possible crash site.
The NASA images, taken on Oct. 20, show two recent changes to the landscape on Mars' surface — one dark blotch, and one white speck — which are being interpreted as Schiaparelli's parachute and its crash site.
With the warning that analysis is still ongoing, here are the details the ESA is sharing Friday:
"Estimates are that Schiaparelli dropped from a height of between 2 and 4 kilometers, therefore impacting at a considerable speed, greater than 300 km/h [186 mph]. The relatively large size of the feature would then arise from disturbed surface material. It is also possible that the lander exploded on impact, as its thruster propellant tanks were likely still full."
That sequence of events followed the lander's largely trouble-free approach to the Martian surface, a trip that was being widely watched on Wednesday, when the craft lost contact with the ESA and its Mars mothership, the Trace Gas Orbiter, just before its touchdown.
It's believed that the Schiaparelli craft successfully navigated its orbital insertion burn and deployed its parachute as planned. But things went awry in the final phase of its landing, as the lander's nine thrusters turned off too early to ease the craft onto the surface.
NASA's Mars Reconnaissance Orbiter captured images of the likely crash site as part of a plan to document and collect data about the lander's arrival to Mars. The new features were easily evident when compared to another image of the same area that was taken in May. Describing the new image, NASA says:
"The area indicated with a black outline is enlarged at right. The bright spot near the lower edge of the enlargement is interpreted as likely to be the lander's parachute, which was deployed and then released during the descent through the Martian atmosphere.
"The larger dark spot near the upper edge of the enlargement was likely formed by the Schiaparelli lander. The spot is elliptical, about 50 by 130 feet (15 by 40 meters) in size, and is probably too large to have been made by the impact of the heat shield."
Despite the loss of its lander, the ESA still has a working science mission in Mars orbit, as the Trace Gas Orbiter will devote itself to studying methane on the red planet. As NPR's Rae Ellen Bichell reported earlier this week:
"Any methane that makes it to Mars' surface would get obliterated by ultraviolet light after a few hundred years. But a few years ago, astronomers looking at infrared images found that methane was released from certain locations on the planet, and that it mostly happened during the warm summer months. In 2013, NASA's Curiosity rover also detected bursts of methane. So, scientists reason, something is actively releasing methane.
It could be some chemical reaction happening underground — like water reacting with a certain kind of rock, or an underground volcanic process. But it could also be a sign of microbes that lived, or live, deep underground.
The Trace Gas Orbiter will spend the next few years mapping out methane on Mars. In theory, it should be able to tell the difference between methane originating from a biological source and methane from a geological source. (Methane from geologic sources should be a little bit heavier.)"
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