Scientists at the European Space Agency (ESA) are facing anxious moments as they wait for data to be sent back from the Philae lander.
The craft should be sending data back from the surface of the comet it started drilling on earlier.
But Philae is also facing an energy problem.
It needs more sunlight to power its solar panels, meaning the ESA team may try to 'hop' it into a more favourable position.
ITV News Science Correspondent Alok Jha reports.
Thsee incredible images show the moment the probe dropped from its satellite and first landed on Comet 67P five days ago.
Scientists racing against time to keep the Philae comet lander operating are debating whether to try 'hopping' the probe to a new location.
After the first man-made craft landed on a moving comet we look at the pictures sent back from the daring descent to the historic landing.