European Schiaparelli Mars probe's parachute 'jettisoned too early'
Europe's Schiaparelli lander did not behave as expected as it headed down to the surface of Mars on Wednesday.
Telemetry recovered from the probe during its descent indicates that its parachute was jettisoned too early.
The rockets it was supposed to use to bring itself to a standstill just above the ground also appeared to fire for too short a time.
The European Space Agency has not yet conceded that the lander crashed but the mood is not positive.
Landing on Mars is always a daunting prospect.
It is necessarily a high-speed approach that has to be got just right or the spacecraft runs the risk of smashing into the ground.
Schiaparelli had a heatshield, a parachute and rocket thrusters in order to slow its approach to the surface.
If the robot is later confirmed as lost, it will clearly be a major blow to Esa which suffered the disappointment of the Beagle-2 lander's failure at Mars in 2003.
But officials here have underlined the fact that Schiaparelli was always viewed within the agency as a technology demonstrator - a project to give Europe the learning experience and the confidence to go ahead and land a more ambitious six-wheeled rover on Mars in 2021.
Mars - a tale of joy and failure
There have been about 15 attempts to get down to the surface of Mars, and they are split fairly evenly between success and failure.
The US space agency has been the most successful with seven successful landings on the Red Planet.
The Soviet Mars 3 probe landed softly but only transmitted data for 15 seconds.
The European Space Agency's last attempt to land on Mars was in 2003, with Beagle 2. But it never sent a signal from the surface.
"This is typical for a test," said Prof Jan Woerner, Esa's director general. "We did this in order to get data on how to land on Mars with European technology. Therefore, all the data we will get this night will be used to understand how to manage the next landing when we go with the rover."
This future vehicle is expected to use some of the same technology as Schiaparelli, including its doppler radar to sense the distance to the surface on descent, and its guidance, navigation and control algorithms.
What will concern commentators is that the budget for the rover is not yet secure. If Schiaparelli is indeed lost, Esa officials may find themselves having to work harder to explain to member states why the extra investment remains worthwhile.
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