Columbia's capture of the telescope is planned for 3:13 a.m. Sunday. The shuttle's final approach will begin this evening with the longest rendezvous engine firing in shuttle program history. The three and a half minute firing, to be performed using the shuttle's two large orbital engines just after 10 p.m., will dramatically slow the rate at which Columbia is closing on the telescope, raising the shuttle's orbital low point more than 200 miles.

In the cockpit, shuttle Commander Scott Altman and Pilot Duane Carey will guide Columbia's approach. On the shuttle's lower deck this evening, Mission Specialists John Grunsfeld, Rick Linnehan, Jim Newman and Mike Massimino will check out and prepare the tools they'll use during five upcoming space walks. Mission Specialist Nancy Currie will power up Columbia's robotic arm, moving it to a position poised to capture Hubble.

The final phase of the rendezvous with Hubble will begin at about 1 a.m. Sunday, when Columbia is about nine statute miles behind the observatory. An engine firing at that time will put the shuttle on course to directly intercept the telescope. As the shuttle moves within about a half-mile below Hubble about an hour and a half later, Altman will take over manual control of the approach. Altman will ease Columbia to within 35 feet of the telescope, within reach of the outstretched 50-foot-long robotic arm.

As Columbia flies 350 miles above the Pacific Ocean east of Australia, Currie will latch the arm onto a fixture on Hubble. Currie will then lower the telescope into position to be latched to a special support structure in the shuttle's cargo bay. The cargo bay Flight Support System, as the structure is called, will hold the telescope for the next week, turning and tilting it as needed for the spacewalking work.

At about 7 a.m. Sunday, commands will be sent to begin retracting the telescope's two solar arrays, one at a time over the course of about two hours, in preparation for Monday's first space walk. The first space walk, which Grunsfeld and Linnehan are planned to begin at about 12:30 a.m. Monday, will install a pair of new-generation solar arrays on the telescope.

The next STS-109 mission status report will be issued Sunday morning or as events warrant.

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