The European Space Agency (ESA) just confirmed that it has soft-landed its Philae probe on Comet 67P/Churyumov–Gerasimenko. After a 10-year mission and a nail-biting seven-hour descent, the signal confirming the successful touchdown arrived on Earth at 16:03 GMT (11:03 EST) on 12 November, 2014. The probe began transmitting data upon landing, and the orbiter craft Rosetta was able to locate and photograph the probe on the comet's surface, visually confirming the success. Click through for the first images of the probe's descent, the first panoramic photo of the comet's surface, and more details about this historic achievement.
Of the successful landing, ESA’s Director General Jean-Jacques Dordain said in a statement: “ESA and its Rosetta mission partners achieved something extraordinary today. Our ambitious Rosetta mission has secured another place in the history books: not only is it the first to rendezvous with and orbit a comet, but it is now also the first to deliver a probe to a comet’s surface.” Stephan Ulamec, Philae Lander Manager at the DLR German Aerospace Center, added: “We are extremely relieved to be safely on the surface of the comet, especially given the extra challenge of the comet’s unusual shape and unexpectedly hazardous surface.”
The probe’s orbiter craft, Rosetta, was launched on 2 March, 2004, and it journeyed 6.4 billion kilometers (3.914 billion miles) before reaching the comet on 6 August, 2014. The comet is an unusual double-lobed object, making the choice of landing site challenging. Data collected at distances of 30–100 kilometers from the comet helped the ESA decide on a landing spot once the orbiter was in place. Rosetta’s first images showed the comet’s surface was littered with boulders and featured towering cliffs, precipices and pits. Jets of gas and dust stream from the surface.
The landing doesn’t appear to have gone completely to plan, however. Three ice screws were supposed to drill down from Philae’s three legs, and two harpoons were supposed to deploy to secure the craft to the surface of the comet, with a thruster counteracting their force. It appears the harpoons may not have fired and that the craft bounced on landing. Given that the probe is in for a bumpy ride in the months ahead as the comet moves closer to the sun, the ESA have an anxious wait for confirmation of how securely the probe is positioned. The probe has 64 hours of battery life to take a panoramic photograph of its new home while taking and analyzing samples from its surroundings. It is also covered in an array of solar panels, and provided it has landed in a well-lit spot as planned – and hasn’t kicked up too much dust on landing that might settle on the panels – it should continue to transmit data and images until March 2015. After that it is expected the comet will become too hot for the probe to continue operating.
Lead image: Rosetta’s lander Philae is safely on the surface of Comet 67P/Churyumov-Gerasimenko, as these first two CIVA images confirm. One of the lander’s three feet can be seen in the foreground. The image is a two-image mosaic. Photos by the European Space Agency – ESA via the ESA website and Flickr