APOD
Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
A Laser Strike at the Galactic Center
Explanation: Why are these people shooting a powerful laser into the center of our Galaxy? Fortunately, this is not meant to be the first step in a Galactic war . Rather, astronomers at the Very Large Telescope (VLT) site in Chile are trying to measure the distortions of Earth's ever changing atmosphere . Constant imaging of high-altitude atoms excited by the laser -- which appear like an artificial star -- allow astronomers to instantly measure atmospheric blurring . This information is fed back to a VLT telescope mirror which is then slightly deformed to minimize this blurring. In this case , a VLT was observing our Galaxy's center , and so Earth's atmospheric blurring in that direction was needed. As for inter-galaxy warfare , when viewed from our Galaxy's center , no casualties are expected. In fact, the light from this powerful laser would combine with light from our Sun to together appear only as bright as a faint and distant star.
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| Date | December 1, 2013 |
|---|---|
| Credit | Image Credit: Yuri Beletsky ( ESO ) |
| Authors & editors: | Robert Nemiroff (MTU) & Jerry Bonnell (UMCP) |
| A service of: |
ASD at NASA / GSFC, NASA Science Activation & Michigan Tech. U. |




