http://gizmodo.com/software-error-implicated-in-crash-of-mars-lander-1788187542
Researchers with the ExoMars mission are pointing to a potential computing
challenge now will be to isolate and correct the error in hopes of preventing a
repeat in 2020, when mission planners aim to land a much larger rover on the Red
Planet.
Late last week, NASA released a grim photograph showing what appears to be the
crash site of the doomed Schiaparelli lander and its discarded parachute. The
lander, if there was ever any doubt, is completely toast, a splotch of burnt and
twisted metal on the Martian surface. So instead of proudly carting out a new
rover, ExoMars planners with the ESA and the Russian space agency Roscosmos are
now having to figure out what the hell went wrong.
Unlike the doomed Beagle 2 mission that was lost in 2003, Schiaparelli
descent. As reported in Nature News, an early look at the data points to a
series of cascading software errors as the reason for the botched landing.
By all accounts the descent started well, with the lander decelerating rapidly
as it brushed up against the Martian atmosphere, eventually deploying its
parachute as planned. But things began to go squirrely just prior to the
five-minute mark of the planned six-minute descent.
For reasons that are still a mystery, the lander ejected both its heat shield
and parachute way ahead of schedule. Schiaparelli then engaged its thrusters for
onboard computer, it would appear, seems to have thought it was close to the
surface. Indeed, Schiaparelli even took the time to switch on some of its
field.
The sad reality is that Schiaparelli was still somewhere between 1.25 to 2.5
miles above the surface when this happened, falling at a rate of about 185 mph
(300 km/h). It struck the ground with tremendous force, resulting in an
different sensors. Some kind of glitch misinformed the lander about its position
in time and space, causing it to execute landing procedures as if it were at a
much lower altitude.
If confirmed, this would actually be good news, as software issues are much
easier to correct than hardware problems. Researchers on the ExoMars team are
replicate the software error using a simulation.
If and when the glitch is detected, a fix will have to be designed, implemented,
prominent part of the mission is scheduled for 2020. This first phase was meant
as a kind of test-run in preparation for the landing of the larger Russian
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