The two residents of the International Space Station (ISS) began a five-hour spacewalk Thursday during which they fixed a radiation-measuring tool and completed other science experiments.

The spacewalk, the first and the only one since the two cosmonauts arrived at the station four months ago, began at 23:00 Moscow time (2000 GMT) Thursday and ended at 3:59 (0059 GMT) Friday, almost an hour ahead of schedule, according to flight controllers in Moscow.

Russian cosmonaut Sergei Krikalev, who was making his eighth spacewalk, and his US partner John Phillips, making his first spacewalk, retrieved bundles of research experiments that were floating outside the Pirs docking compartment.

They also installed a television camera that will be needed when Europe's new cargo vessel makes its debut flight to the ISS.

In their final task, the two cosmonauts collected "matryoshka," the Russian name for a traditional nesting doll that they use to refer to a radiation-measuring tool.

The tool is a space doll, a close-to-lifesize torso made of soft material to simulate human tissue, with embedded sensors to measure radiation exposure.

A two-hour chore -- to remove a crane attachment from the side of the station -- had to be dropped because the cosmonauts were running out of time.

With his current space station stay, Krikalev sets a new record for staying the longest in space. He beat the previous record set by fellow Russian Sergei Avdeyev, who spent 747 days and 14 hours in space over the course of his career.

Krikalev and Phillips are expected to return to Earth in October after completing their mission.

Source: Xinhua