The primary goal of today's spacewalk, to be conducted by Mike Foale and European Space Agency astronaut Claude Nicollier, is to install a new computer to replace the one currently in use by Hubble. The new computer is 20 times faster and has six times the memory of the outdated unit being replaced. Nicollier and Foale also will change out one of Hubble's three Fine Guidance Sensors that are used to precisely point the telescope as it conducts scientific observations. The unit being installed today is a refurbished unit that was removed and returned to Earth by the STS-82 crew during its servicing of the telescope in February 1997. If time permits, the space walkers also may perform some optional "get ahead" tasks. Foale has conducted two previous spacewalks, during the STS-63 mission in February 1995 and again in September 1997 as he and Mir Space Station Commander Anatoly Solovyev conducted a six-hour survey of the Mir. This is Nicollier's first spacewalk.
Today's spacewalk is scheduled to begin at 1:50 p.m., but could begin earlier if the crew members complete their preparations ahead of schedule. During the spacewalk, Foale can be recognized by the broken red stripes on the legs of his EVA suit, and Nicollier by the diagonally broken red stripes on his suit.
Discovery's astronauts also supported a functional test of the voltage temperature improvement kits - referred to as VIKs - installed by Steve Smith and John Grunsfeld during their spacewalk yesterday. To ensure the checkout is complete prior to the start of today's scheduled EVA, the astronauts began the work shortly after crew wake-up. During the 90-minute long checkout, investigators will monitor the performance of the voltage kits as the telescope's batteries are charged.
This morning's wake-up music honored the two space-walking astronauts, Nicollier and Foale. Traditional Swiss music was played for Nicollier and the song "Only When I Sleep" by The Corrs was played for Foale.
Discovery remains in excellent condition, in an orbit with a high point of 380 statute miles and a low point of 369 miles.