The Philae comet probe has run out of power, but not before radioing back to Earth to confirm successfully drilling into the body of the comet.
Due to a failure to anchor itself to the comet the robotic lander bounced after its initial landing on Wednesday, eventually coming to rest in the shadow of a cliff 1km from its original target landing zone, which has put its ability to recharge a secondary battery using solar panels in doubt.
With the 60-hour life of the primary battery fading yesterday, scientists decided to send commands for Philae to attempt to use its drill to obtain samples from the comet's body despite the fact that the ultra-low gravity meant torque from operating the drill could cause the lander to float free again.
But Philae was able to use a communication window yesterday to transmit a message to the orbiting Rosetta mothership containing telemetry data showing that its drill successfully operated, descending more than 25cm below the comet's surface.
"First comet drilling is a fact!" Esa, which is running the Rosetta mission, posted on Twitter on Friday night.
Results from the drilling are still pending, but Esa reported on its Rosetta blog last night that the lander’s batteries are now depleted and it has gone into 'idle mode' in which all instruments and most systems on-board are shut down.
Contact with the lander was lost just after midnight, not long before the mothership orbited below the horizon of the comet, which would have severed contact anyway.
"Prior to falling silent, the lander was able to transmit all science data gathered during the First Science Sequence," said lander manager Stephan Ulamec. "This machine performed magnificently under tough conditions, and we can be fully proud of the incredible scientific success Philae has delivered."
Further contact with Philae will only be possible if enough sunlight is gathered by the lander’s solar panels, something made more likely by news that the craft had successfully rotated 35 degrees in a bid to expose more panel area to the Sun.
The Rosetta orbiter will listen for a signal during a communication slot at 10am this morning and will continue to do so whenever its orbit makes contact possible as comet 67P/Churyumov-Gerasimenko continues on its journey towards the Sun.
After a 10-year flight, Rosetta arrived at the comet in August for a mission that is expected to run at least through December 2015.
"This mission is fantastic, let's look at what we have achieved, not at what we would have done differently. This is unique and will be unique forever," said Rosetta flight director Andrea Accomazzo.