Exhausted and Exhilarated, HUT Team Digging Into Data By Emil Venere Now that the Astro-2 mission has come to an exciting conclusion, the scientific intrigue is just beginning, as Hopkins astronomers face a new kind of pressure. A special session on Astro-2 findings has been scheduled for a meeting of the American Astronomical Society in June. But before the Hopkins team can even begin preparing their presentations, they have to wade through the mountain of data collected by the Hopkins Ultraviolet Telescope. Members of the HUT team said they are excited with anticipation about what they hope to learn from the observations, but they aren't making any predictions. "A huge amount of work has to go into this to get it right," said Arthur Davidsen, an astrophysicist who heads the Hopkins Ultraviolet Telescope project. The observatory was operated within the payload bay of the space shuttle Endeavour during a record 16 and a half day mission that ended March 18. After returning to Hopkins, exhausted scientists took a few days off before hitting their computer terminals. "I was pretty beat when I got back," said Dr. Davidsen, a professor in the Department of Physics and Astronomy. He slept only about three hours each night of the mission. One thing is certain: the hard work paid off. HUT's data are high quality, promising to yield valuable information about the astronomical targets observed by the orbiting telescope, said Gerard Kriss, HUT's project scientist. By using a spectrograph to study ultraviolet light, astronomers can learn many details, such as composition, temperature and velocity of objects. HUT detected a range of light called the far ultraviolet spectrum, which is not visible to other telescopes and enables observations of some of the most energetic phenomena in space. But astronomers can't begin writing about their findings until the data are put through a complex series of conversions so that they can be interpreted. The data also have to be corrected for interference caused by radiation, called "airglow," from Earth's upper atmosphere. HUT collected about 30 compact discs' worth of information-- a massive amount of data considering that an encyclopedia can fit on one CD. "It's clearly a treasure trove of information," said William Blair, another astrophysicist on the project. NASA has provided enough money for two and a half years of data analysis, Dr. Kriss said. But the project has produced enough material to keep scientists busy for a decade. HUT astronomers collected four to five times as much data as they did with Astro-1, which flew aboard the space shuttle Columbia in 1990. Chief among HUT research is the search for an "intergalactic medium" of helium and hydrogen, presumably produced in the Big Bang. HUT astronomers were successful in collecting data that could prove critical in efforts to find out whether such material really exists and, if it does, to calculate how much is present. "Although there's a lot of work ahead, this is the fun part, finding out what it all means," Dr. Blair said.