Problems reported with shuttle's observatory


GREENBELT -- Problems with a telescope pointing system have delayed by at least 12 hours the start of astronomical observations by the Hopkins Ultraviolet Telescope and three others aboard the space shuttle, Columbia scientists said today.

"We have lost about 15 to 20 pointings at this time, which we will not recover," said mission scientist Ted Gull, of the Goddard Space Flight Center. About 230 pointings were planned during the 10-day mission.

The shuttle is scheduled to return to Earth on Dec. 11 at 9 a.m.

Hopkins scientists today did manage to take their first scientific reading with the Hopkins Ultraviolet Telescope -- the first by any of the four astro telescopes.

Spokeswoman Lisa Hooker said the scientists at 11:30 a.m. took a spectrographic reading of the fringes of Earth's atmosphere above the shuttle. The chemical data it revealed must be figured into any data received later from stars and galaxies.

"Getting started is taking a lot longer than we anticipated," Gull said, adding that "I don't think I've ever seen a telescope come in on schedule."

Mission manager Jack Jones said new computer commands had improved the performance of star trackers in the pointing system. But more refinements were to be transmitted to the spacecraft late today.

"It's a very complex system, and we had to get it . . . deployed and free of gravity before we could get everything back into alignment," Jones said. "This is an expected phenomenon we would have to work with any star tracker."

The pointing system is similar to one that gave scientists trouble on a 1985 shuttle mission. If it can't be made to work properly, Jones said, controllers can switch to another, less precise pointing system on board.

Technicians were also working to correct alignment problems on the Broad Band X-ray Telescope, which is mounted on a swivel separate from the ultraviolet telescopes.

But the Hopkins Ultraviolet Telescope itself and the three others that make up the $148 million Astro Observatory were all reported to be "up and ready to go" once the pointing problems are fixed.

Problems with a balky computer inside the Wisconsin Ultraviolet Photo Polarimeter Experiment were fixed earlier today, Jones said.

The Hopkins telescope and two other ultraviolet instruments in the shuttle's payload bay all depend on the same Instrument Pointing Systems that technicians were trying to fix.

Hopkins scientists said the system must guide their telescope to the bright star Capella, 40 light-years from Earth in the constellation Auriga, so that they can finish focusing the instrument, the last step before beginning scientific observations.

"HUT is still working fine. We're just waiting on the IPS [instrument pointing system]," said Hooker.

The Astro Observatory is designed to explore some of the hottest and most violent regions of space, which generate radiation in the X-ray and ultraviolet wavelengths.

Among the first targets the telescopes will seek are the brightest quasar in the sky, called 3C273, Supernova 1987A and the Crab Nebula, which is the brightest source of x-rays in the sky.

Baltimore astronaut Samuel T. Durrance was said to be "cool as a cucumber" on board Columbia today as he worked to get the Hopkins telescope ready to explore the stars from the orbiter's cargo bay.

The Astro observatory was rocketed into orbit early yesterday after more than 12 years of planning and 4 1/2 years of flight delays.

The near-perfect launch, monitored from the Goddard Space Flight Center here, was followed by yesterday's telescope test.

Last night, the Columbia crew and mission controllers successfully opened the Hopkins telescope's delicate spectrograph to the harsh vacuum of space. But because of the pointing problems, HUT was unable to find Capella.

Still, using one of the ultraviolet telescopes during a test last night, the crew focused on the "first light" -- a star called Beta Doradus that was selected for testing purposes, not scientific observation.

"Everyone is gathering around the Christmas tree," said Stu Clifton, an assistant mission manager at the Marshall Space Flight Center in Huntsville, Ala., where most of the data from the shuttle are being gathered.

The long-delayed mission was launched at 1:49 a.m. yesterday in a spectacular nighttime liftoff that brought tears to Arthur Davidsen's eyes.

"My knees were shaking and my heart was pounding," said Davidsen, the principal investigator on the HUT project for the past 12 years. He watched the launch at Cape Canaveral, Fla., before flying to Huntsville.

Samuel T. Durrance, a Hopkins research scientist who lives with his wife and two young children in Lutherville, is one of two Marylanders aboard Columbia helping operate the four Astro telescopes during the 10-day mission.

Durrance is assigned to operate HUT during the 12-hour day shift.

His wife, Becky, was in Florida yesterday to watch the launch.

The second Marylander on board Columbia is Ronald A. Parise, of Burtonsville, a senior space observatory scientist with Computer Sciences Corp., in Silver Spring.

Parise is responsible for the Ultraviolet Imaging Telescope, developed at Goddard.

The other telescopes in Columbia's payload bay are the Broad Band X-ray Telescope, developed at Goddard, and the Wisconsin Ultraviolet Photo-Polarimeter Experiment, developed by the University of Wisconsin at Madison.

All four telescopes will be returned to Earth with the shuttle landing scheduled for 9 a.m. Dec. 11 at Edwards Air Force Base in California.

Data from all three ultraviolet telescopes were being relayed to Marshall, where the scientists who developed each instrument were gathered to review the data and direct activity on board the space craft.

More than 20 scientists from Johns Hopkins were in Huntsville working on the Hopkins Ultraviolet science team.

The Broad-Band X-ray Telescope was being operated remotely by scientists at Goddard.

Until now, Gull said, each of the telescope teams has had to rely on sub-orbital "sounding" rockets to get their instruments above Earth's atmosphere, which blocks most ultraviolet and X-ray radiation from space.

Because of the short duration of such flights, they could accumulate only a few hundred seconds of observation on each flight.

From the Astro Observatory, they will enjoy hundreds of thousands of seconds of target observation time, with the added advantage of a far more stable platform for their telescope.

For example, HUT will collect more than 300,000 seconds of observations on nearly 200 objects.

When Columbia rose from the launch pad early yesterday, it drew cheers and applause from a crowd of several hundred people, many of them physics and astronomy students, watching on a big-screen video at the Bloomberg Center for Physics and Astronomy at Johns Hopkins University.

Besides Durrance and Parise, the shuttle's crew includes Vance D. Brand, commander; Guy S. Gardner, pilot; and mission specialists John M. "Mike" Lounge, Jeffrey A. Hoffman and Robert A.R. Parker.

The crew, split into "blue" and "red" teams, will man the Astro telescopes in two 12-hour shifts for the duration of the 10-day mission to maximize observation time.

On Friday, Durrance will participate in a "space classroom" program.

Students from the Gwynn Park Middle School in Prince George's County and the Hammond Middle School in Howard County will speak with the crew from special classrooms at Goddard.

Plans called for the students to discuss ultraviolet astronomy with Durrance and other crew members.

The seven Columbia crew members were followed into space yesterday by a crew of two Soviets and a Japanese journalist aboard a Soviet Soyuz spacecraft headed for the Mir space station. Mir is already occupied by two Soviet cosmonauts.

That makes a total of 12 humans in space this week, which NASA called a record.

The Associated Press contributed to this story.

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