Wednesday, May 13, 2009

Live In Orbit: Shuttle Atlantis Speeds Toward Hubble

The Atlantis astronauts just entered the final stage of a ground-up rendezvous with the Hubble Space Telescope and they are on track to snatch the observatory from orbit at 12:54 p.m. EDT.

Flying Atlantis some 50,000 feet -- or 9.5 miles -- behind Hubble, shuttle skipper Scott "Scooter" Altman fired the spaceship's left orbital maneuvering engine for just 12 seconds.

The so-called "Terminal Initiation burn," or "TI burn," initiated the final stages of a rendezvous that began with the precisely timed 2:01 p.m. launch of Atlantis from Kennedy Space Center on Monday.

"Atlantis, Houston," astronaut Dan Burbank called up from the Mission Control Center in Houston. "Good burn. No further trim required."

"Copy, Houston," Altman replied. "No trim required."

The call meant the firing came off perfectly and no course correction would be required at this time. The flight plan calls for up to four mid-course corrections during the final stage of the rendezvous. Those may or may not be required.

The 12-second engine firing was designed to raise the shuttle's orbit to match that of the telescope -- one 349 miles above the planet.

Atlantis mission specialist Megan McArthur is limbering up the shuttle's 50-foot robot arm, the mechanism she'll use to grapple a pin-like fixture on the side of the telescope.

The TI burn and any course corrections are aimed at bringing Atlantis to a point about 600 feet from the telescope.

Altman then will climb out of the commander's seat on the left hand side of the orbiter's cockpit and float to its aft flight deck work station.

Standing there with joystick-like controls in his hands, Altman will eyeball the Hubble from through overhead windows as well as windows that provide a direct view of the cargo bay. Then he'll gently pulse shuttle thrusters to move Atlantis within about 30 feet of the telescope.

The close proximity operation will give McArthur the opportunity to latch onto Hubble's pinlike grapple fixture with snares in the end of the shuttle's robot arm.

The 12.5-ton telescope then will be mounted on a work platform at the aft end of the shuttle's cargo bay about 1:41 p.m.

You can watch the action unfold live here in The Flame Trench. Simply click the "Live Shuttle Broadcast" box at the righthand side of the page to launch our NASA TV viewer and live coverage.

Be sure to refresh this page, too, for periodic updates.

All major mission milestones are listed here in Rev B of the NASA TV Schedule.

A more detailed look at the crew's timeline is here in the Flight Day 3 Execute Plan

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