A computer terminal that allows astronauts to communicate with a trio of ultraviolet telescopes on the space shuttle Endeavour failed briefly yesterday and threw a scare into astronomers.
But the balky "data display system" was turned off, switched on again and has been working fine ever since, said Bill Blair, deputy project scientist with the Hopkins Ultraviolet Telescope (HUT).
He is with the HUT ground team at the Marshall Space Flight Center in Huntsville, Ala.
The glitch was a haunting reminder of problems that canceled half the observations planned for the three telescopes' first mission, Astro 1, in 1990.
But start-up work on the $445 million Astro 2 mission, to gather data and photographs from hundreds of objects in light frequencies never seen before, appeared yesterday to be running pretty much as planned.
"We're almost on the mission time line, and so it looks like by early morning we should at least be attempting to do some of our first science," said Dr. Blair.
Endeavour blasted off on its 16-day astronomy mission just a minute late, at 1:38 a.m., climbing to an orbit that will keep it too far south to be visible from Maryland.
Among the crew of seven are Dr. Ronald A. Parise, 43, of Silver Spring, an astronomer with Computer Services Corp.; and Dr. Sam Durrance, 51, of Lutherville, a Hopkins astrogeophysicist.
In Huntsville, where the HUT ground support team is working 24 hours a day to coordinate and evaluate the observations, scientists were elated.
Forecasters had warned of delays, but the clouds cleared long enough for launch.
"It was exciting," Dr. Blair said. "We got off on time, and that was a big boost.
"It cuts down on the amount of work we need to do to get into our science mission."
In 1990, Astro 1's telescopes were supposed to find and lock on to targets automatically.
When the pointing system failed, astronauts were forced to do the pointing manually. There were no backup systems.
During checks yesterday, Dr. Blair said, the revamped system was "doing exactly what it was supposed to do."
"Not only is it acquiring [stars] on automatic, but in two backup modes," he said. "It also has the capability to lock on and hold."
Yesterday's 90-minute scare came when one of two computer terminals that communicate with the telescopes failed to turn on properly.
On Astro 1, both terminals overheated and failed, forcing scientists to control the internal workings of the telescopes from the ground.