The Columbus space lab installed on Monday was brought online and there are no problems so far.

"There is no problem whatsoever. We have the basic power, the light, the computer system" working on Columbus, said Alan Thirkettle, a space station (ISS) official for the European Space Agency, as quoted by Agence France Presse. "We are looking to get really into the full activation so the crew can take off their masks."

Thus almost everything seems to be working as expected after the complex lab was powered up. For the first time, French astronaut Leopold Eyharts opened the hatch to the lab at 1408 GMT on Tuesday. He was joined shortly by the commander of the ISS, US astronaut Peggy Whitson. They wore special protective goggles and face masks to protect them from free-floating particles which may have been set free from the gravity which kept them bound to the underside of the lab while on Earth.

The European Columbus laboratory has been successfully attached to the Harmony module on the International Space Station at 22:44 CET on Monday, after a seven-hour, 58-minute spacewalk by Mission Specialists Rex Walheim and Stanley Love, who were responsible for bolting the Power and Data Grapple Fixture (PDGF) to the Columbus module.

Meanwhile, German astronaut Hans Schlegel is feeling much better. His undisclosed health problems have led to the postponement of the first spacewalk from Sunday to Monday. "Medical issues are private," he said, announcing that he will join American astronaut Rex Walheim for a six- to seven-hour spacewalk today.

They have to replace a nitrogen tank that pressurizes an external space station cooling system that circulates ammonia through the station's solar power network.

The third spacewalk is scheduled for Friday, when astronauts Love and Walheim will attach a pair of science experiments to the outside of the new lab.

It took a while before the space shuttle Atlantis was successfully launched – two months of continuous delays and uncertainties – but the mission finally took off last Thursday for the International Space Station. It is for the second time in seven years that the ISS receives a science laboratory, after the U.S.-built Destiny Laboratory Module, activated in February 2001.

About 25 years in the making, Europe's Columbus space laboratory was finally launched on Thursday. The event occurs just 15 years late of its original launch date. The 17-nation European Space Agency developed the Columbus starting in 1982, aiming to launch it in 1992, to celebrate the 500th anniversary of the great navigator's voyage to the New World.

The $2 billion lab will allow experiments to be conducted on the behavior of weightless liquids, and on micro-organisms, cells and tissues.

Columbus is designed for ten years of operation and will be controlled by the special Columbus Control Centre, located at the German Space Operations Centre, part of the German Aerospace Center (DLR). On May 27 last year, the Columbus lab was flown from Bremen to Kennedy Space Center on board an Airbus Beluga.