Astronauts to enhance Hubble’s visionary outlook

Associated Press

CAPE CANAVERAL, Fla. – After 12 years on the job, the Hubble Space Telescope is about to get a scientific makeover and the cosmic equivalent of a caffeine jolt.

It all begins Thursday with the launch of space shuttle Columbia on a servicing mission that is being billed as the most challenging yet. At least five spacewalks are planned, each one crucial to the makeover.

The formidable work falls to four astronauts: a pair of physicists, a mechanical engineer and a veterinarian skilled in surgery on elephants, rhinos, whales and walruses.

“It’s like doing surgery on a big beast, that’s the way I look at it,” said astronaut-vet Richard Linnehan. “I’m going in to make the Hubble better than it was.”

The four men will install an advanced camera and try to resuscitate another, replace damaged solar wings and an unreliable steering wheel and, in the toughest and most nerve-racking job of all, pull out the original, faltering power-control box and plug in a new one.

Before the spacewalkers try to pry off 36 connectors on the old power unit – which was never meant to be replaced – the telescope must be powered down completely for the first time ever in orbit.

“It kind of violates a longstanding policy in the space business that if something’s working well, you don’t turn it off and just hope it comes back on,” said Ed Weiler, NASA’s space science chief. “We’re not doing that cavalierly. We fully anticipate that everything will work fine. But it is a risk that we’ve never faced before.”

If all goes well, the new power-switching station will control and distribute the outpouring of electricity generated by Hubble’s fresh solar wings, smaller than the ones they will replace but considerably more efficient. This combo should give the observatory a tremendous energy boost.

Hubble also should end up with better vision for beholding the universe.

The $76 million Advanced Camera for Surveys that’s going in will enable Hubble to observe more with every sweep of space, with better-than-ever clarity and speed. Astronomers expect to increase the telescope’s imaging capability by 10 times.

The Johns Hopkins University team that built the camera said if the optical instrument was in Washington, D.C., it could discern two fireflies 6 feet apart in Tokyo.

Johns Hopkins astronomer and team leader Holland Ford said the rejuvenated Hubble may be able to uncover planets orbiting other stars and help determine when galaxies began to form in the first billion years of the universe.

Hubble’s prowess will be further enhanced if Columbia’s astronauts manage to revive an infrared camera that has been dormant for three years. The camera’s detectors stopped working when the nitrogen ice needed to keep them at minus-350 degrees was depleted prematurely.

The spacewalkers will hook up a new type of mechanical cooler that uses neon gas in an attempt to bring the infrared camera back to life. NASA stresses it is an experiment, and isn’t making any promises.

After three successful servicing missions, including the first in 1993 to correct Hubble’s blurred vision, NASA worries it may have set the bar too high.

“Every time we do a mission and pull it off, then that becomes the standard. Then everything is, ‘Well, you did that and didn’t have any problems, so let’s put 5 percent more on this one,’ ” said mission director Phil Engelauf.

Just one more service call is planned after this one, in 2004. The space agency said it cannot afford any more.

NASA has spent nearly $7 billion on Hubble since its development, including the shuttle visits. The telescope alone exceeds $2 billion, although NASA astronomy director Anne Kinney is quick to point out that it’s priceless.

The numbers back her up: Hubble has taken 420,000 exposures since its 1990 launch, observed 17,000 astronomical targets and yielded more than 3,200 scientific papers. Findings include the confirmation of black holes.

“Hubble is an American comeback story. We went from it being a metaphor for failure to a metaphor for we-can-fix-it,” Ford said.

NASA’s plan, for now, is to bring Hubble back on a shuttle in 2010 for display at the Smithsonian Institution’s National Air and Space Museum. By then, the Next Generation Space Telescope, set for launch in 2009, should be flying and beaming down even more stupendous views of the universe.