NASA Conducts Key Shuttle Payload Key Test

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NASA is marching through a major payload test today as the agency and its shuttle fleet operators gear up for the planned May 11 launch of shuttle Atlantis and seven astronauts on a mission to service the Hubble Space Telescope.

With the 18-story spaceship perched on launch pad 39A at Kennedy Space Center, NASA and United Space Alliance are in the midst of a two-day test aimed at verifying electrical connections between shuttle payload elements, their carriers, the orbiter and the flight deck.

The Integrated Verification Test began today and is scheduled to be completed Tuesday. An end-to-end test of communications links between the cargo, the shuttle, NASA's Launch Control Center and NASA's Tracking and Data Relay Satellite system will follow later this week.

The tests are expected to be complete by the time senior NASA managers meet for an executive-level Flight Readiness Review on Thursday.

NASA will hold a press conference after the conclusion of the review, and you can watch it live here in The Flame Trench. The briefing is scheduled for no earlier than 6 p.m. Thursday, and you can click the NASA TV box at the right hand side of this page to launch our NASA TV viewer and live coverage.

The Atlantis astronauts plan five spacewalks on consecutive days to service the Hubble Telescope for a fifth and final time.

Nestled in the shuttle's cargo bay is a variety of gear that includes:

++Two new state-of-the-art science instruments: the Widefield Camera 3 and the Cosmic Origins Spectrograph.

++New batteries to replace original equipment that has been operating since the observatory was launched aboard Discovery 19 years ago.

++New gyroscopes designed to keep the observatory flying in a stable manner -- a capability critical to precisely pointing at celestial objects.

The astronauts also plan to repair two telescope instruments: the Advanced Camera for Surveys and the Space Telescope Imaging Spectrograph.

The crew includes mission commander Scott Altman, pilot Gregory "Ray Jay" Johnson and five mission specialists: robot arm operators Megan McArthur and spacewalkers John Grunsfeld, Andrew Feustel, Mike Massimino and Mike Good.

The astronauts are due in at KSC on May 8 -- the same day the countdown for launch picks up at the nation's shuttle homeport.

ABOUT THE IMAGES: Click to enlarge the NASA images of the payload bay of shuttle Atlantis, which now is filled with the equipment and hardware needed to service the Hubble Space Telescope. The cargo was transferred to launch pad 39A earlier this month. Launch of Atlantis' mission to Hubble is targeted for May 11. The flight will include five spacewalks during which astronauts will refurbish and upgrade the telescope with state-of-the-art science instruments. As a result, Hubble's capabilities will be expanded and its operational lifespan extended through at least 2014. Photo credit: NASA/Jack Pfaller.