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Flexible mirrors and yellow lasers for better telescopes

Esquire, one of those "Magazines for men", is running an interesting article on the work on adaptive optics and directed energy being done at the U.S. Air Force's Starfire Optical Observatory. Big AO telescopes use a smart flexible mirror, one that can match the distortions of atmospherically whacked light waves with equal but opposite bends in its surface.

This works great when aimed at bright objects beaming down enough distorted light to measure, but for a space-surveillance system or a versatile astronomical tool it's not enough. For this, a laser guidestar is used, like an artificial star movable in the sky, available wherever needed. By bouncing a laser beam off air molecules and measuring the turbulence with the reflected light, the scopes can look anywhere.

And now, Starfire's latest guidestar, from the laser team led by Craig Denman, is a new and improved guidestar generated by a yellow-photon laser that excites sodium atoms fifty-six miles high in the mesosphere. It can reflect off a diffuse band of meteorite debris, and from that higher altitude return a better beam, at a truer angle, for even bigger telescopes.

Nice to see that in these magazines you can find more than half naked girls, cars, health and fashion articles... ;)

posted by Goto @ 14:46