| STS-71 | Crew | Payload | Mission | Contact and Capture | Rendezvous |
STS-71
Space Shuttle Atlantis
100th U.S. human spaceflight missionLaunched:
June 27, 1995, 3:32 p.m. EDT
Kennedy Space Center, Pad 39-A
Orbit:
170 nautical milesInclination:
51.6 degreesLanded:
July 7, 1995, 10:54 a.m. EDT
Kennedy Space CenterMission: 9 days, 19 hours, 22 minutes
STS-71
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| STS-71 | Crew | Payload | Mission | Contact and Capture | Rendezvous |
STS-71 Crew
Commander Robert L. "Hoot" Gibson
Fifth Shuttle flightPilot Charles J. Precourt
Second Shuttle flightMission Specialist Ellen S. Baker, M.D.
Third Shuttle flightMission Specialist Bonnie J. Dunbar, Ph.D.
Fourth Shuttle flightMission Specialist Gregory J. Harbaugh
Third Shuttle flightCosmonaut Anatoly Y. Solovyev
Russian Space Agency
First Shuttle flight; remaining on MirCosmonaut Nikolai M. Budarin
Russian Space Agency
First Shuttle flight; remaining on MirAstronaut Norman E. Thagard, M.D.
Fifth Shuttle flight; returning from MirCosmonaut Vladimir N. Dezhurov
Russian Space Agency
First Shuttle flight; returning from MirCosmonaut Gennady M. Strekalov
Russian Space Agency
First Shuttle flight; returning from Mir
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| STS-71 | Crew | Payload | Mission | Contact and Capture | Rendezvous |
Payload
Spacelab/Mir Science
Metabolic Research
Cardiovascular and Pulmonary Research
Neurosensory Research
Hygiene, Sanitation, and Radiation Research
Behavior and Performance Research
Fundamental Biology Research
Microgravity Research
Protein Crystal Growth Experiment
IMAX Cargo Bay Camera
Shuttle Shortwave Amateur Radio Experiment
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| STS-71 | Crew | Payload | Mission | Contact and Capture | Rendezvous |
Mission: June 27 - July 7, 1995
With STS-71, NASA staged a space opera that outdazzled the popular movie Star Wars. This mission presented gleaming spacecraft, galactic vistas, precision flying, nerves of steel, and onboard diplomacy between two superpowers who had recently been at odds. It also included a cast of 10 crewmembers in space (six astronauts and four cosmonautsùthe most for one mission) and hundreds of team members on Earth, speaking two languages.
STS-71 featured the first Shuttle "changeout" of Mir crews and the return of U.S. astronaut Norm Thagard from his U.S. record-setting, paradigm-breaking, nearly four months onboard the Russian space station. And, to share the experience with audiences on Earth, STS-71 went "wide screen" and captured the adventure on large-format IMAX film.
It was serious business, this first docking of a Space Shuttle to the Mir, but the drama and thrill of this historic event could not be denied. Indeed, Pilot Charlie Precourt said the sight of arriving at Mir reminded him of "science-fiction movies, where Luke Skywalker is flying in on his ship and lands on the big station à because thatÆs really what youÆre seeingùthis outpostùagainst black space [and] this huge planetÆs horizon in the background. And, if you just take your imagination one step further, you are arriving from another galaxy to this space station outpost in some other solar system."
According to Precourt, "You can put yourself in that little world fairly easily. To see à a little speck grow into something that has shape and realize there are people living in that thing is pretty phenomenal."
For the docking, Commander Hoot Gibson positioned Atlantis directly below Mir, so that the EarthÆs gravity naturally braked the OrbiterÆs approach "up" to Mir. He and his crew executed a nearly perfect docking, off by less than one inch and one-half degree. Together, Atlantis and Mir totaled almost 500,000 pounds, the largest structure ever assembled in space.
After docking, the two commanders met in the docking tunnel for handshakes and greetings. Shortly after, both crews gathered in the Mir Base Block for a ceremony. On Flight Day 4, in Spacelab with the Russian and U.S. flags as a backdrop, the STS-71 and Mir crews exchanged ceremonial gifts. Together, they rejoined a halved pewter medallion bearing a relief image of a docked Shuttle and Mir space station.
After transferring responsibilities from the Mir-18 to the Mir-19 crew, joint operations included scientific investigations and the transfer of gear and supplies between the two spacecraft. The Atlantis crew retrieved from Mir samples of urine, saliva, blood, and water as well as a broken Salyut-5 computer. They transferred to Mir custom spacewalking tools to repair a jammed solar array on the Spektr module; nitrogen and oxygen to raise MirÆs air pressure; and more than 1,000 pounds of water for waste system flushing and electrolysis.
Under Payload Commander Ellen BakerÆs direction, STS-71 conducted a full-scale scientific campaign, using nearly three tons of science equipment in Spacelab. Mir-18Æs research in seven medical and scientific disciplines concluded during STS-71. Eleven experiments remained on Mir to be conducted by the Mir-19 crew. These experiments would investigate the cardiovascular and pulmonary systems; neurosensory effects; hygiene, sanitation, and radiation; human behavior and performance; fundamental biology; and microgravity.
When the time came for undocking on July 4, 1995, the Mir-19 crew temporarily left Mir in their Soyuz spacecraft to videotape the separation, which looked like a "cosmic ballet," according to Commander Gibson.
For reentry, Mir-18 crewmembers Thagard, Dezhurov, and Strekalov lay in the mid-deck of the Atlantis in custom-made Russian seats designed to ease their transition back into gravity. The Mir-18 crew had exercised intensively to prepare for the stresses of reentry and gravity after more than three months in space. Their changes in pulse, blood pressure, voice, and posture were monitored during the reentry portion of STS-71.
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| STS-71 | Crew | Payload | Mission | Contact and Capture | Rendezvous |
Contact and Capture: Emotions of the Moment
"I remember sitting there the day that Hoot [Gibson] maneuvered the docking system in and called down, æContact and capture.Æ I had a lump in my throat for the rest of the day. I really did. It was à so historical.
"The last time we actually docked [during] Apollo-Soyuz, it was a different time, it was a different place, and we werenÆt necessarily friendly. This time it just had an overwhelming impact on me.
I was amazed at my emotional responseà. The rest of the dayùthe training teamùwe just walked around. We were all kind of in a daze because we had trained these people to do this, and they had gone up and done it perfectlyà.
"All of the hard work and everything paid off."
û Lisa Reed, Lead Docking Trainer for STS-71 at Johnson Space Center
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| STS-71 | Crew | Payload | Mission | Contact and Capture | Rendezvous |
Rendezvous & Docking
Moving a spacecraft around in orbit is not as easy as one might think. A physical principle called orbital mechanics makes getting around in space very different from getting around on Earth. Astronauts cannot simply point the spacecraft in the direction it needs to go and then fire the rockets.
Furthermore, the nearly 100-ton Shuttle has a lot of momentum. A Shuttle may appear weightless in microgravity, but its mass makes it act somewhat like a barge on a riverùhard to change direction and hard to stop. Also, the masses of Mir and of a Shuttle are great enough that, according to calculations astronaut Mike Foale once did, even if the two spacecraft were "parked" in orbit 30 feet apart, their own gravity would pull them together in the span of a few hours.
Basically, an Earth orbit can be compared to "falling" around the Earth. The spacecraftÆs flight path can be described as continuously arching downward at precisely the curvature of the Earth.
Orbits of different heights have different set speeds. Lower orbits are faster; higher orbits are slower. This can be compared to the different speeds of a leaf going down a drain. The leaf circles the drain slowly at first; then it spirals faster and faster as it gets nearer the drain. MirÆs orbit was higherùand slowerùthan a typical Shuttle orbit.
Once a spacecraft has achieved an orbit, that orbit will not change unless the upper atmosphere slows it down or some energy is applied with rockets or jets. Therefore, to match ShuttleÆs orbit with MirÆs, astronauts must use the principles of orbital mechanics.
STS-71Æs June 29, 1995, rendezvous and docking with Mir actually began with the precisely timed launch of Atlantis on a course for the station. Atlantis had a "launch window" of precisely 10 minutes and 19 seconds. Missing this window would make it impossible to link up with Mir. Over the first two days of the mission, Commander Hoot Gibson and Pilot Charlie Precourt made periodic small engine firings, gradually bringing Atlantis to a point eight nautical miles behind Mir. On the third day, they fired a terminal phase initiation burn, and the ShuttleÆs rendezvous radar system began tracking Mir to provide range and closing rate information to the Shuttle crew. As Atlantis neared Mir, the trajectory control sensorùa laser ranging device mounted in the payload bayùsupplemented the ShuttleÆs onboard navigation information.
Onboard Atlantis, the crew started watching for Mir. According to Precourt, Mir "starts out as a little star, so itÆs kind of exciting to see whoÆs going to be the first on the crew to spot [it]. WeÆll be maneuvering, and we know where it should be, so IÆll yell out to everybody, æOkay! Look out this window. See if you can see it.Æ Then we see it, and we call the ground, æHey, weÆve got them in sight. We see themÆùthis twinkling little star out there. Then you can follow them as you go around from the sunlit side to the dark side, and you can see, with each successive [revolution], them starting to get larger and larger."
Atlantis proceeded to a point directly below Mir, along the Earth radius vector (R-bar), which is an imaginary line drawn between the Mir center of gravity and the center of the Earth. Approaching Mir from directly below allowed natural gravitational forces to slow the approach more than would occur during a typical Shuttle approach from directly in front of a satellite. The R-bar approach also reduced the need for jet firings close to the MirÆs solar panels and the Soyuz capsuleÆs navigation surfaces.
About one-half mile below Mir, STS-71 Commander Hoot Gibson took over manually. He flew the Shuttle using the aft flight deck controls, located below the windows looking back into the payload bay. Using a centerline camera fixed within the docking system in the payload bay, Gibson centered the ShuttleÆs docking mechanism with the MirÆs docking device, which was positioned on the end of the Kristall science module. He continually refined this alignment as the Shuttle approached to within 300 feet of the station.
Gibson held Atlantis at a "station-keeping" distance, 250 feet from Mir, while flight directors in Houston and outside Moscow reviewed the status of the two space vehicles. When he got a "go" for final approach, Gibson maneuvered Atlantis at a rate of 0.1 feet per second until the Shuttle was 30 feet away. During the station-keeping period and the final approach, the Shuttle crew radioed the Mir crew, keeping them informed of events from that point on. The final approach ended 216 nautical miles above RussiaÆs Lake Baikal region, with a nearly perfect dockingùoff by less than one inch and 0.5 degree.