A team of astronauts has anchored a giant, billion-dollar Japanese laboratory to the International Space Station.The lab is named Kibo, Japanese for hope, and at 37 feet (11m) long is bigger than the US and European labs already attached to the space station.During a scheduled six-and-a-half-hour spacewalk, two astronauts prepped the lab for installation by removing power and heating cables and restraints that connect it to the shuttle.Astronauts working from inside used the space station's robot arm to lift the lab from the shuttle and anchor it to the station.The start of the spacewalk was delayed nearly an hour as a faulty communications cap - which allows spacewalkers to talk with other crew members and controllers on the ground - was replaced.Despite the delay, Lead Spacewalk Officer, David Beaver, said they were able to get through a list of planned tasks.The Japanese lab has a pair of robot arms, the larger of which flew up on this shuttle mission.A separate storage room loaded with Kibo equipment went up in March.A porch for outdoor science experiments and the smaller robot arm will be taken up next year.