April 29, 2011
The plucky few who work near the chilly summit of Mauna Kea were witnesses this week to a sight straight out of sci-fi movies: The first dual laser launches by the W. M. Keck Observatory’s twin 10-meter telescopes. The new laser system on Keck I uses the latest Free Space Transport mirror technology to fire a more powerful laser into the sky. The two lasers excite a layer of sodium atoms about 60 miles up which scintillate like a pair of artificial stars. The twinkling of those artificial guide stars reveals how Earth’s turbulent atmosphere is constantly distorting star light. With this information astronomers can use Keck’s Adaptive Optics system to cancel out the distortions at a rate of 2,000 times per second. The result is that Keck Telescopes can see deep space objects with a clarity that rivals space telescopes.