Man made star helps scientists adjust their vision.

On a clear night, a broad band of stars sweeps across the sky, backed
by the faint, milky glow of even more stars. This is the Milky Way and
on a midsummer eve the very center of it can be picked out within the
Sagittarius constellation. But even on the clearest night, the earth’s
atmosphere obscures the true brilliance of our galaxy and astronomers
have long struggled with images blurred by its mix of gases and
turbulence. Now researchers have used a new laser-generated star to
obtain the clearest pictures yet of the Milky Way’s center.

Astronomer Andrea Ghez of the University of California, Los
Angeles, and her colleagues used the 10-meter Keck 2 telescope in
Hawaii, which has a laser attached to it, to observe our galaxy. The
skywatchers employed the 14-watt laser to generate a fake star. By
continuously imaging this false star along with the real ones, they
could correct any fuzziness or other distortions introduced by the
earth’s atmosphere. "We used a laser to improve the telescope’s
vision," Ghez explains. "It’s like getting LASIK surgery for the eyes,
and will revolutionize what we can do in astronomy."

By David Biello

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