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- SPACE, Page 66Galactic Birth?
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- A surprise for scientists
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- Astronomers have long believed that galaxies, clusters that
- usually contain billions of stars, were all formed shortly
- after the Big Bang, the cataclysmic explosion some 15 billion
- years ago that spawned the universe. But that conviction was
- shaken last week when scientists announced that they had found
- evidence of a cosmic version of gestation: a galaxy preparing
- for birth. Said James Gunn, a Princeton University
- astrophysicist, after the announcement: "This is the Rosetta
- stone of galaxy formation."
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- The apparent galactic embryo -- actually a massive,
- disk-shaped cloud of hydrogen gas -- was discovered fortuitously
- last spring by Cornell University astronomer Martha Haynes and
- her colleague Riccardo Giovanelli, when they were monitoring
- signals in outer space with the 1,000-ft. radio telescope at
- Arecibo, Puerto Rico. While focusing the telescope on what they
- thought was empty space in order to calibrate it, the
- astronomers picked up a signal pattern resembling that emitted
- by galaxies. The invisible cloud -- estimated to be ten times
- as large as the Milky Way -- loomed fairly close, astronomically
- speaking: 65 million light-years from earth. Since a light-year
- is the distance light travels in a year, the scientists were
- receiving signals from the cloud as it appeared 65 million years
- ago. Because it apparently contained no stars, the scientists
- concluded that they were observing a galaxy about to be born.
- Said Giovanelli: "This cloud indicates that galaxies can form
- slowly throughout the history of the universe and are not just
- something that happened during some magical period in the
- distant past."
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