Space Station Construction Resumes with Successful Atlantis Mission

By Cheryl Pellerin
Washington File Staff Writer

Washington - Space shuttle Atlantis and its six-member STS-115 crew glided to a landing early on September 21 at Kennedy Space Center in Florida, completing a successful mission to resume construction of the International Space Station and a journey of 7.8 million kilometers.

The flight was the first in a series of missions that will be among the most complex in space history. Atlantis delivered the first major new component to the station since 2002 and laid the groundwork for upcoming station assembly missions.

“It’s really a beautiful day in Florida, a great way to end the mission,” said Commander Brent Jett, after performing a walk-around inspection of the vehicle with his fellow astronauts.

“It was a pretty tough few days for us, a lot of hard work,” he added, “and a great team effort to get the station assembly restarted on a good note.”

Jett’s crewmembers were pilot Chris Ferguson and mission specialists Joe Tanner, Heidemarie Stefanyshyn-Piper, Dan Burbank and Steve MacLean - a Canadian astronaut.

Canadian Prime Minister Stephen Harper called MacLean during the mission to congratulate him on being the first Canadian to operate Canadarm2, the station's Canadian-built robotic arm.

STATION ASSEMBLY RESUMES

Atlantis launched September 9 and arrived at the station two days later. The crew delivered the P3/P4 integrated truss segment to the station and conducted three spacewalks mainly devoted to preparing the truss and its solar arrays for operation.

The 15.9-metric-ton truss will provide power and data services for the station. The solar arrays, unfurled September 14, span 73 meters and will double the station’s power-generation capability when they are operational.

With Atlantis and its crew safely home, the stage is set for the next phase of space station assembly.

Preparations continue for space shuttle Discovery's launch, targeted for mid-December, on the STS-116 mission to deliver another truss segment and a cargo module to the station. Discovery also will do extensive work on the station's electrical and cooling systems.

 “We’re back into more of the normal operational tempo now,” said NASA Administrator Mike Griffin during a post-landing press briefing in Florida.

“We’ve got data that we’ve never had before, we understand the tank and its issues and its performance better than we ever have before,” he added. “I’m very confident that we will complete the assembly of the space station on schedule by 2010.”

STS-115 was one of the most-photographed shuttle missions, with more than 100 high-definition, digital, video and film cameras documenting the launch and climb to orbit.

Data from these images, and station and shuttle crew inspections, helped clear Atlantis’s thermal protection system for return 2.5 days after launch.

THE MISSION

Tanner, Piper, Burbank and MacLean, with the help of crewmates, made three spacewalks that completed truss installation, enabled solar arrays to be deployed and prepared an important radiator for later activation.

They also installed a signal processor and transponder that transmits voice and data to the ground, and performed other tasks to upgrade and protect the station's systems.

A new procedure called a "camp out" was implemented, in which astronauts slept in the Quest airlock before their spacewalks.

The process shortens the "prebreathe" time, during which nitrogen is purged from the astronauts' systems and air pressure is lowered so the spacewalkers avoid a decompression illness called the “bends.”

On each of the three spacewalks, the astronauts performed more than the number of scheduled activities.

The astronauts also did some unprecedented robotics work. They used the shuttle's robotic arm in a delicate maneuver to hand off the school-bus-sized truss to the station's arm. The 13.7-meter truss weighs 15,875 kilograms.

The arrays at the end of the truss extended to their full 73-meter wingspan once they unfurled on flight-day six. The astronauts also moved the station's arm to a position where it will help in the next phase of station construction.

NEXT STEPS

After Atlantis undocked from the station, it did the first full fly-around of the facility since before the space shuttle Columbia accident in 2003. The maneuver helped ground crews get a better perspective on the station’s environment and exterior health.

After undocking, the Atlantis crew participated in a first-ever three-way call with the Expedition 13 crew aboard the space station and the three crewmembers of the Soyuz spacecraft on its way to the station. All 12 astronauts in space at that time were able to have a conversation.

“We’ve had a lot of people on orbit this last week,” said Lynn Cline, NASA deputy associate administrator for space operations. “In addition to STS-115 completing its mission this morning, on orbit right now we have Expedition 13 handing off to Expedition 14.”

Commander Michael Lopez-Alegria and cosmonaut Mikhail Tyurin of the 14th International Space Station crew docked at the station in the early morning hours of September 20 to begin a six-month stay on the orbiting laboratory.

With Tyurin at the controls, their Soyuz TMA-9 spacecraft docked smoothly at the aft port of the Zvezeda service module. They launched from the Baikonur Cosmodrome in Kazakhstan early September 18.

With them was Iranian-American businesswoman Anousheh Ansari, the first female spaceflight participant - a paying private space explorer - to visit the station. She is flying under contract with Roscosmos, the Russian Federal Space Agency.

She will return to Earth September 28 with the Expedition 13 crew, commander Pavel Vinogradov and NASA science officer Jeff Williams, who welcomed the new arrivals.  Expedition 13 launched to the station March 30.

The third Expedition 14 crewmember, European Space Agency astronaut Thomas Reiter of Germany, also greeted the new crewmembers. Reiter arrived at the station aboard Discovery on the STS-121 mission in July.

Reiter joined Expedition 13, bringing the number of station crewmembers to three for the first time since May 2003. He will remain on board as a member of the Expedition 14 crew.

“You’ll also see, from the crew that we’ve had up there the last week, the exercise of our international partnership and how important that is to us, with a Russian, European and American crew on the station and a Canadian-American crew on the shuttle,” Cline said.

“All these things help us learn to live and work in space, and do it on an international basis,” she added. “It’s a great foundation for our future exploration.”