UMass Amherst Astronomers Help Open New Window on the Formation of Stars

December 16, 1998


AMHERST, Mass. - Astronomers from a half-dozen institutions, including the University of Massachusetts, are looking at the universe in a new light with NASA’s launch of the Submillimeter Wave Astronomy Satellite (SWAS). The information provided by the satellite will be used to study the conditions that lead to the birth of stars, a process now hidden in clouds of dust and gas in space.

University of Massachusetts astronomers Ronald Snell and Neal Erickson watched from mission control at Vandenberg Air Force Base in California earlier this month as the spaceborne observatory, attached to a rocket, was dropped from the belly of a modified L-1011 aircraft, then shot into space, reaching orbit 10 minutes later. The observatory orbits the Earth every 97 minutes, and relays information to a ground station twice a day. Ground stations are located in Poker Flat, Alaska, and Wallops Flight Facility in Virginia.

"The mission’s goal is simple," said Snell. "We’re looking for key molecules in space." The satellite contains a small submillimeter-wave telescope designed to search for water and molecular oxygen. These molecules are significant coolants of the interstellar clouds, and can provide information about the clouds’ composition and chemistry, said Snell. Knowledge about the abundance of these life-sustaining molecules may also shed light on how they are incorporated into the atmospheres of newly forming planets, he added.

SWAS "sees" into the dense clouds by searching for submillimeter-wavelength radiation - a band between radio and infrared waves on the electromagnetic spectrum. The submillimeter-wave detectors were built at Millitech Corp. in South Deerfield, a UMass spin-off company which Erickson helped found. Submillimeter emissions cannot easily be studied from the ground, even at mountain-top or airborne astronomical observatories, because of interference from the large quantities of water and molecular oxygen in Earth’s own atmosphere, Snell said. At an orbital altitude of 400 miles above earth, SWAS will have an unobstructed view of the heavens.

Other institutions involved in the project include the Harvard-Smithsonian Center for Astrophysics, Cornell University, NASA Ames Research Center, Johns Hopkins University, and the University of Cologne, Germany. The satellite weighs only 625 pounds, and is one of NASA’s Small Explorers (SMEX) satellites, designed and built to be small and economical, yet scientifically powerful. The prime contractor for the scientific instrumentation was the Ball Aerospace and Technologies Corp. in Colorado. The spacecraft was built at NASA’s Goddard Space Flight Center, Maryland.