Shuttle finishes linkup with space station

December 14, 1998
by Paul Hoversten

HOUSTON -- Space shuttle Endeavour is on its own today after gently pushing away from the International Space Station on Sunday, ending a historic week-long linkup in orbit.

Super view: Endeavour commander Bob Cabana, left, and pilot Rick Sturckow watch as the space shuttle moves away from the International Space Station. The shuttle astronauts are scheduled to return to Earth Tuesday night after completing a seven-day mission to link modules Zarya, from Russia, and Unity, from the United States.

Pilot Rick Sturckow fired Endeavour's steering rockets at 3:24 p.m. ET to move the shuttle away from the 34-ton, 76-foot-long station at less than 0.5 mph.

Then he flew a slow circle and a half around the station from 440 feet out so his crew mates could photograph it shimmering in the blackness of space.

"This has been a truly awesome experience," Endeavour commander Bob Cabana radioed Mission Control just before the undocking. "It's going to be one heck of a space station when we get it done."

"You folks have done it right," Mission Control's Chris Hadfield replied.

Ground controllers got their first look at the station as Endeavour circled about 245 miles above the northern Pacific at dawn.

Frank Culbertson, NASA's deputy station chief, likened the station's historic significance with that of Apollo 8, the first manned trip around the moon, which flew 30 years ago this month.

United: NASA video shows Zarya, bottom, joined with Unity.

"This hardware is the foundation of what will put humanity in space forever," he said.

Endeavour's astronauts are scheduled toland at Florida's Kennedy Space Center at 10:56 p.m. ET Tuesday.

The shuttle transported the station's second piece, a connecting tunnel called Unity, into space. Last Sunday, Endeavour's crew attached Unity to the station's first piece, a Russian power component called Zarya, which was already in orbit.

Together the two pieces form the cornerstone of what is planned to be a 100-piece, 460-ton station when finished in 2004. Until Sunday, the shuttle had remained attached to the space station's first two pieces.

NASA and its 15 international partners hope to use the space station as a world-class laboratory for new discoveries in medicine, biology and industrial manufacturing.

	What have the astronauts accomplished in the last week? Would you consider their mission a success? Why or why not? What is left to be done so that the International Space Station is completed? Why is teamwork and cooperation even more important in space than in an average earthly setting? Try it! Write a short scene for a story about the astronauts working on the ongoing International Space Station. Use technical information from the article to make your story ring true. Then, introduce a minor or major crisis into your story scene, and try to resolve it!

Seven U.S. shuttle crews are training to build the station in orbit and four other crews are training to occupy it. The first crew to live aboard the station is to arrive in January 2000, and the station is to be manned continuously for 10-15 years after that.

The next space shuttle to visit the station will be Discovery, which is set to be launched in May. It will bring more supplies to furnish the station's interior.

Two Discovery astronauts also will make a spacewalk, the first of 10 to be made during four shuttle flights in 1999 to assemble the station.

Sunday's undocking wrapped up a busy weekend. The shuttle crew turned off the station's lights and closed it Friday after spending 28 hours inside. Then on Saturday night, astronauts Jerry Ross and Jim Newman made their third and final spacewalk, this one to free a stuck Russian docking antenna on Zarya and finish outfitting the station.

The two men spent 21 hours on the three spacewalks during this mission. That gives Ross the U.S. spacewalk record for a shuttle astronaut. Ross, 50, has logged slightly more than 44 hours on seven spacewalks.

With the shuttle safely away, ground controllers in Houston commanded the station to adjust its position and fly with Unity facing Earth to afford maximum communication through its antenna.

Then they put the station into a slow spin that turns it around once every 30 minutes to ensure that its sensitive electronics get neither too hot nor too cold.

The internal temperature of Unity will be allowed to drop to minus 35 degrees. Zarya, which has computer and solar arrays that generate electricity, will stay between 64 and 84 degrees.

The two sections are sealed off from each other by hatches that the Endeavour crew closed Sunday.