European probe readies for historic landing on a comet

European scientists launched a probe from the spaceship Rosetta on Wednesday in a historic attempt to examine the surface of a comet, starting a seven-hour descent that is seen as the most difficult phase of a 10-year mission.

The European Space Agency earlier gave the final go ahead for separation of the Philae lander from Rosetta, which has been orbiting comet 67P/Churyumov-Gerasimenko since August.

"Now it's up to gravity to bring it down," said Stefan Ulamec, Philae Lander Manager at the DLR German Aerospace Center.