Shuttle Astronauts to Dock at Space Station

A camera on the shuttle's robotic arm captured this image of Discovery's payload bay and crew cabin on July 6, 2006 during Flight Day 2 of the STS-121 mission. CREDIT: NASA TV.

HOUSTON - The seven astronauts aboard NASA's space shuttle Discovery will begin their third day in orbit on their own today, but will end it with friends once they dock at the International Space Station (ISS).

Discovery's STS-121 astronaut crew is set to arrive at the space station at about 10:52 a.m. EDT (1452 GMT) during a docking that is eagerly awaited by ISS Expedition 13 commander Pavel Vinogradov and flight engineer Jeffrey Williams. The two spacecraft crews will meet at the end of a two-day trip for Discovery that began at launch on July 4.

"Obviously, that will be a good time," Williams said earlier of the prospect of having nine people living aboard the ISS.

Vinogradov and Williams were able to watch Discovery's STS-121 mission launch into orbit via a television hook-up, but have had a busy few days preparing their orbital home for its first human guests of Expedition 13. They not only made space for the fresh supplies Discovery is bringing to the station, but also sorted out trash or unneeded material to make the return trip to Earth.

"It's very crowded on the station and stowage is an issue," Williams said before Discovery's flight. "So we also need to get a lot of stuff off."

Last week, the space station astronauts also welcomed an unmanned Russian cargo ship - Progress 22 - which docked at the aft end of the orbital lab's Zvezda service module on June 26 with its own shipment of cargo to be sorted and stowed.

"We will have to work hard, but it is a pleasure dealing with this challenge," Vinogradov said.

Led by veteran spaceflyer Steven Lindsey, the STS-121 Discovery crew is hauling well more than 5,000 pounds (2,267kilograms) of food, equipment, spare parts and other supplies to the ISS. Also aboard is third ISS crewmember - European Space Agency (ESA) astronaut Thomas Reiter of Germany - to return to station back to a full crew. ISS crewswere scaled down to two astronauts, beginning with Expedition 7 in April 2003, after NASA's Columbia shuttle tragedy.

Williams said he's looking forward to the STS-121 crew's arrival, not the least of which because the shuttle contains astronauts from the U.S. Navy and Air Force. Williams himself is an Army man.

"Steve Lindsey has asked if he could bring an Air Force banner," Williams said before the STS-121 crew launched into orbit. "I welcome all of that kind of thing. It's a lot of fun and good sport, plus we have football season coming soon so we're looking forward to that kind of rivalry."

Photo inspection on tap

Before Discovery can dock at the ISS, the Expedition 13 crew must complete a photographic survey of the shuttle's tile-lined belly.

Using high-resolution digital cameras, Vinogradov and Williams will each snap a preset series of photographs of Discovery's heat-resistant tiles as Lindsey guides the shuttle through a back flip known in NASA circles as the Rendezvous Pitch Maneuver.

Discovery will be about 600 feet (182 meters) from the ISS when Lindsey puts the shuttle through its orbital acrobatics at about 9:52 a.m. EDT (1352 GMT). Vinogradov and Williams will use 800 mm and 400 mm digital still cameras to photograph Discovery's tile-lined undercarriage at resolutions of between one and three inches, respectively.

Image analysts on the ground will pore through those photographs to determine if any of the numerous small black tiles along Discovery's undercarriage were damaged by debris during launch.

"We'll have our early assessment of the underside of the vehicle, the tiles of the vehicle," said John Shannon, NASA's deputy shuttle program manager, of the planned Rendezvous Pitch Maneuver photography during a Wednesday press briefing here at NASA's Johnson Space Center.

Third astronaut's a charm

Also bearing down on the ISS along with Discovery is Reiter, a German astronaut and the first non-U.S. or Russian spaceflyer to take an extended flight to the orbital research laboratory.

But Reiter's status as the third member of Expedition 13 won't be final until his Soyuz seat liner is transferred into place aboard the Russian-built Soyuz TMA-8 spacecraft that brought Vinogradov and Williams to the ISS on April 1.

"As soon as my seat liner is there, I will be an official member of the station crew," Reiter said in a NASA preflight interview.

Transferring the seat liner is one of Reiter's first activities and currently scheduled to occur at 2:02 p.m. EDT (1802 GMT).

Reiter is expected to serve aboard the ISS through the remainder of the Expedition 13 mission and the first half of the Expedition 14 mission, which is currently set to launch on Sept. 16. He is also slated to return to Earth in December during Discovery's STS-116 shuttle mission, NASA said.

"I think this moment signifies that we are getting back on track, if I may say so," Reiter said before launch. "There has been an interruption of three years where only two people were working on board the station, and now we are actually back in a state that we can continue with the assembly."

NASA will broadcast Discovery's ISS docking beginning at 5:08 a.m. EDT (0908 GMT). You are invited to follow along with the STS-121 and Expedition 13 crews using SPACE.com's NASA TV feed, which is available by clicking here.

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