Shuttle Endeavour Crew Arrives at Space Station

HOUSTON - The space shuttle Endeavour successfully docked with the International Space Station (ISS) Friday, merging two excited astronaut crews hundreds of miles above the South Pacific Ocean.

The shuttle's STS-118 astronaut crew arrived at the orbital laboratory at 1:02 p.m. EDT (1702 GMT), after the station's three-man Expedition 15 crew photographed Endeavour's heat-resistant underbelly with digital cameras. Hatches opened between the two spacecraft just after 4:04 p.m. EDT (2004 GMT).

"Welcome aboard," said Expedition 15 commander Fyodor Yurchikhin as Endeavour's crew hooked up to the space station.

The docking marked the orbital arrival for teacher-astronaut Barbara Morgan, who helped prime Endeavour's docking ring for connection with the ISS. Morgan's flight comes 22 years after she was first selected as NASA's backup Teacher in Space in 1985.

Commanded by veteran shuttle flyer Scott Kelly, Endeavour's seven-astronaut crew is hauling about 5,000 (2,267 kilograms) of fresh cargo to the ISS, as well as an external spare parts platform and new addition to the space station's starboard-side truss.

Step by step

Endeavour's Friday ISS arrival came after a two-day cruise that began with a Wednesday launch from NASA's Kennedy Space Center (KSC) in Florida. Kelly took the 100-ton orbiter's helm, guiding it within nine miles (14 kilometers) of the space station by firing a correctional burn of propellant.

"We're waitin' for ya," ISS crewmember Clay Anderson radioed to Kelly shortly after the maneuver.

When Endeavour arrived 625 feet (191 meters) below the orbital laboratory, Kelly fired small thrusters on the spacecraft, rotating the shuttle in place to expose its black underbelly to the ISS crew. Midway through the zero-gravity somersault, the station's Expedition 15 astronauts snapped photographs of the shuttle's heat-resistant tiles for relay down to Earth.

After the orbital acrobatics, Kelly swung Endeavour up to the forward part of the space station to dock in front of its U.S. Destiny laboratory.

Rushed greetings

Not long after the two astronaut crews meet, however, astronauts began preparing for at least seven busy work days in space--but could tack on three days to the mission.

The possible extension hinges on tonight's 5:51 p.m. EDT (2151 GMT) test of the Station-to-Shuttle Power Transfer System (SSPTS). The new device is designed to allow Endeavour to draw on the space station's solar power grid and conserve its fuel cell resources. Mission managers here at Johnson Space Center (JSC) will decide Sunday whether or not to extend the mission.

Despite the potential for more time in space, however, shuttle astronauts Tracy Caldwell and Rick Mastracchio wasted no time preparing the station's new Starboard 5 (S5) spacer truss for delivery. The two will hand off the 4,000-pound (1,814-kilogram) hunk of space station, affectionately known as "Stubby," to the ISS' robotic arm later today.

"The S5 truss is just one of many things that need to be done," Morgan said in a NASA interview. "We hit the ground, or we hit the space, running, and we don't stop until we land."

Once the truss is in position, STS-118 mission specialist Dave Williams and Mastracchio will be primed for their first spacewalk tomorrow. The busy rush of post-docking isn't a new experience for some of the STS-118 astronauts.

Two members of Endeavour's crew, Mastracchio and pilot Charlie Hobaugh, are making a return trip to the ISS. Hobaugh helped deliver the station's U.S. Quest airlock during NASA's STS-104 mission in 2001, one year after Mastracchio and his STS-106 crewmates primed the orbital laboratory for its first astronaut crew.

"When I was onboard the space station it was only three modules last time. Nobody was living there and it was nice and clean, so I expect it to be just as clean as when I left it," Mastracchio said jokingly in a preflight interview.

• VIDEO: Teaching the Future: Teacher-Astronaut Barbara Morgan
• VIDEO: Endeavour's STS-118 Mission Profile
• Complete Space Shuttle Mission Coverage