Saturn's moon Daphnis up close
Impact on the comet's surface occurred 14.5 hours after its descent manoeuvre; the final data packet from Rosetta was transmitted at 10:39:28.895 UTC (SCET) by the OSIRIS instrument and was received at the European Space Operations Centre in Darmstadt, Germany, at 11:19:36.541 UTC. The spacecraft's estimated speed at the time of impact was 3.2 km/h (2.0 mph; 89 cm/s), and its touchdown location, named Sais by the operations team after the Rosetta Stone's original temple home, is believed to be only 40 m (130 ft) off-target. The final image transmitted by the spacecraft of the comet was taken by its OSIRIS instrument at an altitude of 20 m (66 ft) about 10 seconds before impact, showing an area 0.96 m (3.1 ft) across. Rosetta's computer included commands to send it into safe mode upon detecting that it had hit the comet's surface, turning off its radio transmitter and rendering it inert in accordance with International Telecommunication Union rules.
“What I look for most of all is an unsolvable problem,” he concluded. “The answer is lost in the past.”
I have never done anything 'useful'. No discovery of mine had made, or is likely to make, directly or indirectly, for good or ill, the least difference to the amenity of the world. I have helped to train other mathematicians, but mathematicians of the same kind as myself, and their work has been, so far at any rate as I have helped them into it, as useless as my own. Judged by all practical standards, the value of my mathematical life is nil; and outside mathematics it is trivial anyhow. I have just one chance of escaping a verdict of complete triviality, that I may be judged to have created something worth creating. And that I have created something is undeniable: the question is about its value.