NASA's Mars Reconaissance Orbiter (MRO) has acquired new high-resolution images of the crashed Schiaparelli lander, following its ill-fated attempt to reach the surface of Mars in one piece. The images confirm that the lander had a very hard fall, and raise new questions about the exact nature of the crash. Image: NASA/JPL-Caltech/University of Arizona
Ever since the European Space Agency's (ESA's) Schiaparelli lander lost contact with Earth on its descent to the surface of Mars last week, an investigation has been underway to determine what the hell went wrong. Schiaparelli was a test craft, intended to demonstrate entry, descent and landing technology that will bring a larger rover to the surface of Mars in 2020 — hopefully, in one piece.
Last week, the MRO's context camera captured a fuzzy image of the site where ESA expected Schiaparelli to land. The image featured a shiny splotch, interpreted to be the lander's jettisoned parachute, and a grim-looking burn mark; the smouldering ruins of the lander itself.
Schiaparelli's crash landing site as seen by the MRO on October 20th. Image: NASA
Now, the MRO has made another pass over Schiaparelli's remains, giving us a better look at the blackened crash site, along with that shiny spot 1.4km south, which is confirmed to be the lander's parachute and rear heat shield. A third feature, about 1.4km east of the impact site, is now suspected to be the front heat shield.
The crash site itself is a bit mysterious. The asymmetric debris field surrounding the crater looks a lot what we'd expect from a meteorite impacting the surface at a low angle. But as ESA notes, Schiaparelli was nearly vertical when its thrusters cut out early. A long dark arc slightly northeast of the crater is also difficult to explain. It's possible that both of these features are related to an explosion in one of the lander's propellant tanks, which were full of unspent fuel upon impact, but further analysis is needed to confirm that hypothesis.
Image: NASA/JPL-Caltech/University of Arizona
The ExoMars team is busy poring over telemetry data sent back from Schiaparelli's mothership, the Trace Gas Orbiter, along with data collected by other orbiters and ground-based telescopes. So far, it seems the descent started well, but that a series of things went wrong in the final minute. First, the parachute and rear heat shield deployed too early, then the thrusters fired ahead of schedule and for a painfully brief three seconds instead of the intended 30.
All signs are pointing toward this being the result of software errors, with Schiaparelli's computer system misinforming the lander as to its exact position in space and time, which caused it to execute a pre-programmed sequence of commands too early. That's actually good news for ESA, because software glitches are easier to resolve than hardware problems.
But the investigation is far from over: Additional imaging by the MRO is planned for the coming weeks, and the data from TGO is still being explored in detail. The ESA expects to have a full post-mortem on Schiaparelli by mid-November.