Repairing Wednesday's failure will require a space walk in coming weeks, NASA said. Another gyro failed two years ago, leaving only one working gyro.

"We cannot control the vehicle without at least two gyros," said NASA maintenance manager Mike Suffredini at the Johnson Space Center in Houston, Texas.

"We are not dealing with a safety issue," he said.

The problem is not the gyroscope itself, but a switch located on the outside of the craft. That requires the space walk, or extra-vehicular activity (EVA).

"The team is looking at the right time and technique to conduct this EVA," he said.

A Russian Soyuz spacecraft docked at the International Space Station Wednesday with three astronauts on board, on the third manned mission to the orbiting craft since NASA halted shuttle flights after the Columbia disaster in February 2003.

American Edward Michael Fincke, Dutchman Andre Kuipers and Russia's Gennady Padalka, who had blasted off two days earlier from Kazakhstan, docked at the station some 400 kilometers (250 miles) above the Earth.

They entered the hatch of the space station some 90 minutes later to be greeted by the two-man crew finishing their six-month mission, who offered them bread and salt, according to Russian tradition.

SPACE.WIRE