Astronauts aboard the U.S. space shuttle Columbia have captured the Hubble Space Telescope in preparation for a week of maintenance by teams of spacewalking astronauts. Columbia will remain in orbit, despite a problem with its cooling system.

After a two-day chase, Columbia caught up with the Hubble and approached it very slowly before astronaut Nancy Currie plucked it from orbit with the shuttle's robot arm.

The observatory will be latched to the cargo bay while two alternating pairs of astronauts service it over five consecutive days of spacewalks beginning Monday.

They will install a more powerful camera, upgrade the telescope's aging electrical system with new solar wings and a generator, add a new gyroscope to aim it, and try to revive a dormant infrared camera with a new cooling system.

Columbia's cooling system gained the faith of shuttle managers Saturday, despite a blockage slowing the flow of refrigerant.

The blockage affected one of two redundant coolant circuits that dissipate heat emitted by equipment. Shuttle officials say the refrigerant flow, though lower than normal, is stable and does not warrant termination of the mission.