When the Space Shuttle Atlantis docked with the Russian Space Station Mir, the two craft formed the largest structure ever assembled in orbit to that time -- approximately 225 tons. While the two spacecraft were linked, the complex became the brightest "star" in the night sky.

Mission Crews

STS-71 Atlantis crew: Commander Robert L. Gibson, Pilot Charles J. Precourt, Mission Specialist Ellen S. Baker, Mission Specialist Bonnie J. Dunbar, Mission Specialist Gregory J. Harbaugh
Mir 19 crew (upload): Anatoly Solovyev, Nikolai Budarin
Mir 18 crew (download): Norman E. Thagard, Vladimir Dezhurov, Gannady Strekalov

The Docking Process

The successful docking of Atlantis and Mir required one of the most exacting series of maneuvers ever attempted in space. It was not unlike trying to screw a 6-foot, 100-ton lid onto a 6-foot, 123-ton jar while both objects were hurtling through space at 17,500 mph. The two specially built connectors had to be lined up within three inches of each other, and it had to happen within two minutes of the appointed time.

The manual phase of the docking process began with Atlantis about a half-mile below Mir. Shuttle Commander Robert "Hoot" Gibson lined up the approach by watching a television screen displaying the view from a camera in the middle of the docking fixture in Atlantis' cargo bay. The rendezvous was also guided by radar and a laser rangefinder that could precisely measure the distance between the approaching spacecraft.

Step 1 As the shuttle closed in on Mir, it broke its own speed by firing propulsion thrusters. Gibson lined up the two parts of the docking apparatus -- one on Mir and one on the shuttle -- by training the camera on a target on Mir's docking base. The capture ring on the shuttle, which extended eleven inches out from the docking base, made contact with a similar ring on Mir.

Step 2 Once the circular fixtures were positioned one against the other, six shock absorbers dampened any remaining relative movements and vibrations.

Step 3 The shuttle's capture ring then extended another three inches to fully align with Mir. The joined section then retracted fourteen inches into the shuttle's docking assembly and was secured with twelve titanium structural latches. The entire docking process took about 1.5 hours.

The seal created by the latched connectors created a vacuum-tight passageway that allowed the seven crew members aboard Atlantis and the three on Mir to float freely back and forth in their shirtsleeves.

Once the mission was over, the latches were unhooked and springs pushed the vehicles apart.

Mission Accomplishments

Fifteen joint biomedical investigations were undertaken, covering seven different disciplines -- cardiovascular and pulmonary functions, human metabolism, neuroscience, hygiene, sanitation and radiation, behavioral performance and biology, fundamental biology, microgravity research. The Mir 18 crew served as the "guinea pigs" for many of these investigations.

Mission Milestones

1) Prior to this mission, the only other time spacecraft from two different nations had met in space was the Apollo-Soyuz mission in July 1975.

2) The launch of Atlantis was the 100th human space launch conducted from Cape Kennedy.

3) This was the first-ever on-orbit changeout of a shuttle crew.

4) The returning crew of eight equaled the largest crew in shuttle history (STS-61A, October 1985).

NASA Shuttle Mission Archives. www.nasa.gov/mission_pages/shuttle/shuttlemissions/archives/sts-71.html

The Mir Space Station

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This page was last updated on 08/10/2011.