Hopkins team prepares launch of observatory

FUSE is 1st major mission created and operated by a university department

June 10, 1999|By Frank D. Roylance | Frank D. Roylance,SUN STAFF

WASHINGTON -- They have $200 million and five years of work riding on a single rocket. But scientists at the Johns Hopkins University say they're confident about the coming launch of their FUSE orbiting observatory -- now less than two weeks away.

"On the day of the count, I will be a little green around the gills," confessed Hopkins astronomy professor Warren Moos, the principal investigator on the project. But he's sure his team has done all it can to ensure that the spacecraft atop the rocket will do its job.

"We've worked and worked, and sweated over it, and tried to think of all the problems," Moos said this week. "We feel pretty good."

FUSE (Far Ultraviolet Spectroscopic Explorer) is scheduled for launch June 23 atop a Boeing Delta II rocket fired from Cape Canaveral Air Station in Florida.

If Moos or any member of his team has been rattled by the five rocket failures the United States has experienced in the past nine months, they're not saying.

"This satellite is totally ready to be launched," said Hopkins' FUSE project manager, Dennis McCarthy.

None of the recent launch failures has involved the Delta II. But two new Delta IIIs and three Lockheed Martin Titan IVs have blown up or carried their military and commercial payloads to useless orbits in recent months.

If all goes as planned, the 3,000-pound FUSE satellite will be lifted into an orbit 480 miles high. After about three months of systems checks and calibrations, it should be ready to begin a planned three years of observations.

FUSE is the first major space science mission that NASA has allowed to be developed, built and operated by an academic department at a university.

In orbit, FUSE will be operated from a control room in the Bloomberg Center for Physics and Astronomy on Hopkins' Homewood campus in Baltimore. In all, the project is expected to pump $96 million into the state's economy.

Its mission is spectrography -- breaking down starlight into 10,000 constituent colors. Patterns in these light spectra can reveal the chemical composition, velocity and temperature of stars and galaxies, or the intergalactic gas clouds illuminated by them.

FUSE was designed to "see" the sky as it appears in the "far ultraviolet" band of the light spectrum. It is invisible to the human eye and can't penetrate the Earth's atmosphere, so astronomers have to rely on orbiting observatories.

One of their first quarries will be an odd form of hydrogen called deuterium.

"Deuterium is a cosmic fossil," said Moos. Its atoms are identical to hydrogen's -- with one proton and one electron each -- except for the addition of a single neutron to each nucleus. All the deuterium in the universe is believed to have been created in the intense heat and pressure of the big bang.

By measuring the relative amounts of deuterium and hydrogen floating in intergalactic space, around distant galaxies and nearby stars, scientists hope to discover the rate at which this primordial material has been reprocessed in stars to form more familiar elements.

Working backward in time, they can then calculate its original abundance.

"If we knew its original abundance," Moos said, "we could figure out the amount of ordinary matter -- the stuff of oceans, people and stars -- that was created [in the big bang]. That's a critical question of cosmology."

FUSE's unique view of the universe will also enable scientists to study how the matter created in stars and blown out into interstellar and intergalactic space is then redistributed throughout the galaxy and the universe.

Those clouds of dust and gas cool, condense and collapse to form the next generation of stars and planets.

For Moos and his team, the coming days will be filled with repeated trips to Cape Canaveral for launch rehearsals and equipment inspections, as the spacecraft is moved to the launch pad and mated with its Delta rocket.

Their most immediate concern is the possibility of more weather-related delays in the liftoff of an unrelated Globalstar-3 communications satellite. The satellite is on the pad next to FUSE and must be launched at least 10 days before FUSE can be cleared to go. Globalstar was scheduled for launch at 9: 48 this morning.

"Our mirrors are sensitive to moisture and humidity," Moos said. Although they're protected from exposure to Florida seaside weather, the longer they sit at the Cape, the greater the chance of an accidental exposure.

Pub Date: 6/10/99

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