Mission engineers at the European Space Agency have failed to make contact with an experimental probe that was due to touch down on the surface of Mars yesterday afternoon.
The lander, named 'Schiaparelli' after the , broadcast data to its mothership during the descent but then it abruptly stopped.
"The signal went through the majority of the descent phase but it stopped at a certain point that we reckon was before the landing," Paolo Ferri, ESA's head of operations, at mission control in Darmstadt, Germany.
"To conclude more on this, because there could be many reasons for that, we need more information," he said. "It's clear that these are not good signs."
Schiaparelli is just one part of the much larger ExoMars project, which has been designed to test technology for future robotic missions to Mars. A rover will also be launched to the planet in 2020, and the lander's mothership – the Trace Gas Orbiter – is already sending back valuable data.
But the engineers must be disappointed, as this isn't the first time they've lost spacecraft on Mars missions. Thirteen years ago, the Beagle 2 rover lost contact in similar circumstances, with showing how close that mission came to success.
Meanwhile, the ESA is looking on the bright side, saying the data Shiaparelli sent back during its descent will be valuable. "If we hadn't obtained that data it would have been a total waste," ESA chief Jan Woerner the Associated Press.
"It's fundamental that we understand what went wrong. We cannot exclude that (it) is safe on the surface and might be in a position to transmit, but I would judge it unlikely."