This explanation is excerpted from Shuttle-Mir: The U.S.
and Russia Share History's Highest Stage.
On June 25, 1997, Vasily Tsibliev took remote control of the Progress
resupply vehicle and fired its rockets to propel the craft toward the
Mir Space Station. In ways, the procedure was similar to playing a video
arcade game. Tsibliev had to virtually "fly" the Progress from onboard
Mir while he watched a video screen that showed an image from a camera
onboard the Progress.
The Progress left its parking orbit and began moving rapidly toward
Mir. But, on the video screen "it was difficult to make out the station,"
according to Tsibliev. The Mir complex "looked very similar to the clouds
below it." Tsiblievís deficient perspective had a further limitation.
According to Mike Foale, "What Vasily was seeing on his screen was an
image that didnít change in size very fast. Thatís the nature of using
a TV screen to judge your speed and your distance. He couldnít determine
accurately from the image that the speed was too high."
By the time Tsibliev could judge the speed, the Progress was already
traveling too fast. He fired the braking rockets, but it was too late.
Aleksandr Lazutkin finally espied the Progress, and he realized the
danger. "Michael, get in the escape ship!" he told Foale. Lazutkin later
described the onrushing Progress as looking "full of menace, like a
shark." He said, "I watched this black body covered in spots sliding
past below me. I looked closer, and at that point there was a great
thump and the whole station shook."
The Progress collided with a solar array on the Spektr module. Then,
the spacecraft hit Spektr itself, punched a hole in a solar panel, buckled
a radiator, and breached the integrity of Spektrís hull.
The collision had knocked Mir into a spin; and the power outage had
shut down the gyrodynes so that the spin now went uncontrolled. To stop
the spin and face the arrays toward the Sun, the crew needed to know
the spin rate of Mir. However, the computer and other instruments were
out of operation. So, in the dark and in the silence, Foale went to
the windows in the airlock and held his thumb up to the field of stars.
Combining a sailorís technique with a scientistís knowledge of physics,
Foale estimated the spin rate of the space station. Then, he and Lazutkin
radioed the estimates down to the Moscow Control Center. The ground
controllers fired Mirís engines, and that stopped the spinócertainly
not perfectly, and in no way permanently; but it showed that it could
The following are computer generated animations of
the collision and the spin that followed and are provided by Analytical
Collision with Mir - MPEG
(13 M) (No Audio)
Spin - MPEG (8 M) (No Audio)
more about Mike Foale and the collision in his Oral History
more about the NASA-5 increment
more computer generated animations of the Mir