The $150 million Astro-1 observatory was poised this morning in the pre-dawn darkness at Kennedy Space Center to end the launch jinx that has delayed it longer than any other space shuttle mission in NASA history.
Columbia was scheduled to lift off at 1:28 a.m. with seven astronauts -- including Johns Hopkins University astrophysicist Samuel T. Durrance -- on a 10-day astronomy mission to study some of the universe's hottest and most violent objects.
Fueling and other preparations proceeded smoothly last night, but a cloud layer that moved over Cape Canaveral yesterday reduced the chances for favorable weather during the 2 1/2 -hour launch window from 70 percent to 30 percent. If the flight is postponed, the National Aeronautics and Space Administration has six days in which to try again before one of the four telescopes aboard must be reserviced.
It was the fifth attempt in six months to launch Columbia, which has been plagued by malfunctions.
"It's obviously been a very long road, and public interest has dwindled a bit," said Theodore Gull, Astro-1 mission scientist. "But I think Astro will shine, for its science discoveries and for our attempts to educate students with this mission."
But the observatory has been in the payload bay for nine months, and Johns Hopkins astronomer Arthur F. Davidsen -- lead scientist for the Hopkins Ultraviolet Telescope -- said, "There are things that can go wrong. The only real test is in orbit."
The first shuttle mission in five years dedicated to science research includes four astronomers: payload specialists Dr. Durrance and Ronald A. Parise of Computer Sciences Corp. in Silver Spring, and veteran astronauts Robert A. R. Parker and Jeffrey A. Hoffman.
Other crew members are Col. Guy S. Gardner of the Air Force, who will be the pilot; mission specialist John M. Lounge and Cmdr. Vance D. Brand, at 59 the oldest astronaut to fly a space shuttle mission. The crew's average age of 47 is the highest in shuttle history.
The astronomers will be operating the observatory round-the-clock in 12-hour shifts. Half the crew began gradually adjusting its sleep patterns during the weeks before launch to man the graveyard shift in orbit 218 miles above the Earth.
Unlike the free-flying Hubble Space Telescope, the observatory will remain fixed in Columbia, exploring ultraviolet light and X-ray radiation from the open cargo bay and then returning home with the shuttle and its crew on Dec. 11.
By rising above the atmosphere, which screens the light from Earth telescopes, Astro-1 could provide important new information about the life cycle of stars and such cosmic mysteries as black holes, quasars and the nature of the vast areas of space between galaxies.
Although the mission will be among the busiest ever flown, NASA has planned an in-flight "Space Classroom" science lesson on the fifth day, shared by middle school students at Goddard Space Flight Center in Greenbelt and at Marshall Space Flight Center in Alabama.
Thirty science students from Howard and Prince George's counties will visit Goddard for a Friday lesson on the electromagnetic spectrum and a live question-and-answer session with the astronomer/astronauts, including Dr. Durrance.