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Telescope Time Lapse



These are the European Southern Observatory's Very Large Telescopes (VLT). Each of the four large telescopes has an 8.2 meter (diameter) primary mirror, and they can be used individually, or they can be combined together to form a much larger telescope through a process called interferometry.

This video also shows the wonders of the Southern Sky. As our Aussie readers can attest, there is a much higher density of stars visible south of the equator owing to the orientation of the Earth relative to the Galactic plane. I've observed once on the Magellan telescopes at Las Companas, Chile, and I can't wait to go back one day soon.

The orange streak emanating from one of the telescopes at 2:44 is the laser guide star adaptive optics system. The laser excites sodium atoms in the atmosphere and forms a fake star above the telescope. The light emitted from this fake star traverses back down through the atmosphere and a sensor on the telescope measures the deviation of the light from a perfect point. Basically, by sensing the twinkling of the fake star, the telescope's camera can adjust its mirror to compensate for the ripples in the atmosphere and form nice, sharp images. There's a laser system like this on Keck, and just last week the Robo-AO laser system was tested successfully at Palomar on the 1.5-meter (60-inch) telescope (see image below).

Comments

blissful_e said…
No wonder telescope time was a huge part of your job negotiations. Wow.

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