See the chase and captureof Hubble (MPEG 1.3 Mb) andhow the telescope willbe secured into the cargo bay (MPEG 1.7 Mb).

Four space walks are planned. The fourastronauts who will be performing the repairs are completely cross-trained,which means any one of them can do any of the scheduled tasks on any day.

The current schedule calls for thefour astronauts to work in teams of two, performing their work on alternatingdays to allow each team a rest day between each space walk.

John Grunsfeld (who will wear a solidwhite spacesuit with no additional identifying markings) and Steve Smith(whose spacesuit will have a solid red stripe) will team together on thefirst and third space walks. Mike Foale (wearing a broken red stripe) andClaude Nicollier (wearing a diagonally broken red stripe) will join forceson space walks two and four.

The plan for the first space walk featuresthe replacement of all three Rate Sensor Units (RSU's), which each housetwo gyroscopes used to point the telescope for observations. Smith andGrunsfeld will also install voltage/temperature improvement kits (VIK)to protect Hubble's batteries from overheating as they get older. Finally,they will open coolant valves and remove caps on the Near Infrared Cameraand Multi-Object Spectrometer (NICMOS) in preparation for work scheduledon the next visit in 2001.

During the second space walk, Foale and Nicollier are scheduled to replace an old computer with a newand more powerful one.

Watch an animation of thecomputer removal and installation (MPEG 1.0Mb), and see where the pieces gowith a cut-away view of the Hubble Telescope (MPEG1.5 Mb).

The plans for the second spacewalkalso include the replacement of one of the Fine Guidance Sensors. Thisrefrigerator-sized box has to be moved slowly and carefully in a weightlessenvironment.
 

There are separate proceduresfor removing the old FGS (MPEG 1.2Mb), replacing it with a newone (MPEG 1.5 Mb), and then storing the old onein the cargo bay (MPEG 1.2 M).

The third space walk includes replacementof an S-band transmitter, installation of another Solid State Recorder,which is more efficient than the old-style tape recorder, and attachmentof new insulation on equipment bays midway up the side of the telescope.

See where the second batchof replacement parts go (MPEG 0.7 Mb), and watch how the transmitterand recorder are replaced (MPEG 1.0 Mb).

The fourth and final planned spacewalk includes activities termed 'Optional Tasks,' because the astronautsmay or may not get to them. For example, one such task is the attachmentof more insulation around the top of the telescope and covers on handrailswith peeling paint. Most of the insulation damage is on the side of thetelescope that always faces the Sun.

See where the new insulationgoes (MPEG 1.5 Mb) and how the astronauts willinstall it (MPEG 0.7 Mb).

Throughout the space walks, the flightsupport system will be rotated so that the area being worked on faces forwardto provide better visibility and access by the robot arm. Then, the HubbleTelescope will be released and redeployed into orbit.

See how the Hubble SpaceTelescope will be replaced in its orbitwhen repairs are complete(MPEG1.2 Mb).