Keeping Their Eyes on the Skies
By Terry Devitt '78, MA'85

Another problem is Earth's location inside the Milky Way. It's like being in the city, says Wilcots, with lights everywhere, and trying to look beyond to see a light in a house in the middle of west Texas. "Being inside a galaxy makes this kind of observation hard to do," he says.

The first observations of the galaxy are to be made with DensePak, one of three instruments on the back end of WIYN to which starlight can be routed from the big telescope mirror. DensePak, a spectrometer, processes starlight that has been bounced from the telescope's mirrors through a tightly packed bundle of fiber-optic cables. The light that passes through each of the cables is routed to a grating that parses it into its constituent wavelengths with more efficiency than the finest prism. The resulting spectra are packed with information, and can tell astronomers more about a star, a galaxy or, in this case, a cloud of glowing gas, than the prettiest, most detailed pictures snapped by the Hubble Space Telescope.

Galaxies tend to clump together and, often, careen into one another, creating what astronomers label, in typical understated fashion, "interacting galaxies." Part of this study, says Wilcots, is designed to sift through that galactic wreckage for clues to how galaxies live, grow, and evolve.

"You can think of a galaxy as a machine, and the purpose of that machine is to make stars," explains Wilcots. "Galaxies that are interacting make more stars. They have a mechanism for collecting gas for star formation. When gas collides, you get star formation."

Sitting at his computer terminal in the WIYN control room, Pisano is thinking about galaxies, too. "I'm studying galaxy formation," he says. He joined the UW-Madison astronomy department five years ago after completing his undergraduate work at Yale. "We don't know much, for instance, about how galaxies evolve when they're in isolated environments." Where, for example, do they get the raw material — gas and dust, mostly — to make new stars? How do these enormous star-making machines develop out of nothing more than amorphous pockets of hot gas?

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