By Irene Klotz
CAPE CANAVERAL, Florida (Reuters) - NASA cleared space shuttle Discovery for a Wednesday launch to complete the International Space Station's power system and deliver Japan's first live-aboard astronaut, officials said on Monday.
Lift off is scheduled for 9:20 p.m. EDT (1:20 p.m. British time Thursday) from the Kennedy Space Centre in Florida.
"Right now we're not tracking any issues," said shuttle launch director Mike Leinbach. "The team is anxious to go."
The weather is expected to be nearly ideal, with a 90 percent chance of suitable launch conditions.
"It should be a really nice night for a launch," said shuttle weather officer Kathy Winters, noting that there will be a full moon rising about an hour before launch.
The shuttle will be carrying a $300 million (217 million pounds) set of solar wing panels for the space station, the last major U.S.-built component for the $100 billion complex.
The station, a project of 16 nations, has been under construction in orbit for more than a decade. It is scheduled to be finished next year.
Discovery also will deliver Japanese astronaut Koichi Wakata, a 45-year-old aerospace engineer who will become the first from his country to serve aboard the station.
"This week will be a historic week for Japan's space program," said Kuniaki Shiraki, executive director of the Japan Aerospace Exploration Agency's human space program. "We have been waiting a long time."
Wakata will replace NASA astronaut Sandra Magnus, who has served as a flight engineer on the station since November.
NASA hopes to expand the station's crew from three to six in May. The Discovery astronauts are delivering replacement parts for the water recycling system, which must be operational before more people can live on the station.
The system, which purifies urine and wastewater so that it can be used for drinking and other purposes, was delivered during the shuttle's last visit in November but has not been working properly.
NASA has eight flights remaining to the space station and a final servicing call to the Hubble Space Telescope before the shuttle fleet is retired.
The Obama administration has requested funding for an additional flight to deliver a dark matter science experiment to the station as long as the mission can be completed before the end of 2010.
NASA is developing a new spaceship called Orion that can travel to the space station as well as the moon. Its first flight is targeted for 2015.
(Editing by Jim Loney and Alan Elsner)
