PLANETARY EXPLORATION:
Europe's Comet Chaser Put on Hold Following Launcher Failure
Govert Schilling
NOORDWIJK, THE NETHERLANDS--The failure last month of an upgraded version of Europe's Ariane 5 launcher has forced the European Space Agency to cancel the planned January launch of Rosetta, a $1 billion science mission. Rosetta was set to perform an unprecedented feat: Catch up with a speeding comet, go into orbit around it, and dispatch a lander to its surface. Now the scientists don't know where they're going--or when.