A German astronaut was greeted aboard the space shuttle Discovery as the crew was awakened Wednesday morning with the upbeat soft rock tune of “Say You’ll Be Mine” by Christopher Cross.

Thomas Reiter of the European Space Agency will get a ride home on the shuttle after spending the past six months at the international space station. Replacing him is U.S. astronaut Sunita “Suni” Williams as the third member of the orbiting space lab’s crew.

“Good morning, Thomas. Welcome to the Discovery crew,” Mission Control astronaut Shannon Lucid. “We are looking forward to seeing you back here on planet Earth just real soon.”

An iffy weather forecast has NASA managers unsure where and when the spacecraft will land. They would like to have Discovery land Friday at Kennedy Space Center, since that would spare the agency the expense of transporting the shuttle back to its Florida home from two other possible landing sites: Edwards Air Force Base in California and White Sands Space Harbor in New Mexico.

At the scheduled landing time, Kennedy was expected to have low clouds and possible showers, while gusty winds were expected at Edwards. White Sands had the best weather forecast on Friday, although that traditionally is NASA’s last choice. During the only landing there in 1982, dust contaminated the orbiter and the brakes were damaged.

“They’re kind of really in a difficult position of deciding where they want to go and when they want to go,” said NASA spokesman George Diller.

If the shuttle can’t land Friday, other attempts can be made on Saturday. Discovery must be on the ground by Saturday or it will run out of the fuel that supplies its electricity.

“Saturday is the last day we can keep it up,” said shuttle flight director Tony Ceccacci.

A day after leaving the space station, Discovery’s seven astronauts on Wednesday were to inspect the shuttle’s heat shield using the spacecraft’s robotic arm attached to a 50-foot boom. The inspection will look for any damage along the shuttle’s nose cap and wings caused in space by micrometeoroids. Engineers on the ground should know within a day after the inspection whether Discovery can be cleared for landing.

A similar inspection was conducted on the second day of Discovery’s mission. Both examinations were added as preventive measures after the Columbia disaster in 2003 killed seven astronauts. Foam from the shuttle’s external tank broke off during lift off, causing a gash in a wing that allowed fiery gases to penetrate the spacecraft during re-entry into the atmosphere.

Astronauts also will release three, small experimental satellites over the next two days.

During eight days at the space station, Discovery’s astronauts made four spacewalks during which they rewired the station’s power system, installed a 2-ton addition and coaxed a stubborn solar panel to fold up accordion-style into its box.

“It’s always a goal to try and leave some place in a better shape than it was when you came,” Discovery commander Mark Polansky said Tuesday before leaving the station. “And I think we’ve accomplished that.”

Several hours after Discovery’s seven astronauts departed Tuesday, station commander Michael Lopez-Alegria radioed to Mission Control that the space lab once again was “pretty roomy up here.”

Mission Control answered back, “And quiet.”

“Well, Suni’s still here,” said Lopez-Alegria, ribbing his new crew mate.

On the Net:

NASA: www.spaceflight.nasa.gov