The European Space Agency's decades-long effort to land a scientific probe on a comet, a feat never attempted before, has been given a final "go" and appears set to proceed with the risky final stages later today.
Experts at the agency's mission control center in Darmstadt, Germany, put the Philae probe through final checks on November 11 and early on November 12.
The robot lab has travelled 6.5 billion kilometers on its mothership, the Rosetta, since the pair were launched more than a decade ago.
But its solo voyage of about 20 kilometers will be the most perilous part.
That is the distance to Comet 67P/Churyumov-Gerasimenko that Philae must cover after separation.
Touchdown is expected to take place about seven hours later, with a confirmation signal sent to Earth.