Taking the Twinkle out of the Night Sky: Breakthrough in Adaptive Optics

[n2doc]

ScienceDaily (Aug. 5, 2010) — If you are like most people, you probably enjoy the twinkling of stars that blanket the sky on a clear summer night. If you are an astronomer, chances are you find it extremely annoying.

A team of University of Arizona astronomers led by Michael Hart has developed a technique that allows them to switch off the twinkling over a wide field of view, enabling Earth-based telescopes to obtain images as crisp as those taken with the Hubble Space Telescope, and much more quickly.

They describe the technique, called laser adaptive optics, in the Aug. 5 issue of Nature.

Atmospheric turbulence blurs the light from celestial objects by the time it reaches the mirror of a ground-based telescope. Most of the distortion happens less than a half mile above ground, where heat rising from the surface ruffles the air.

Think of laser adaptive optics as noise-canceling headphones, only for light waves instead of sound waves. A bundle of laser beams and a pliable mirror in the telescope optics form the heart of the system.

From their observatory on Mount Hopkins south of Tucson, Ariz., Hart and his group point a bundle of green laser beams into the night sky. Some of the laser light bounces off oxygen and nitrogen molecules high up in the atmosphere, creating five artificial stars spread across the field of view.

more
http://www.sciencedaily.com/releases/2010/08/100804133354.htm


While this region of Galactic Globular Cluster M3 appears to harbor only a few fuzzy stars when viewed through conventional ground-based telescope optics (left), laser adaptive optics brings out the fainter stars and makes the image sharper (right). (Credit: Photo by M. Hart)

[WillParkinson]

1. Now that's cool!

Thanks for sharing this.

[caraher]

2. I didn't realize this was only just being adopted

I wonder how many observatories are going to be doing this in the next several years? (I didn't read the article...)

[n2doc]

3. They have been doing a variant on this for a while

The early methods used 1 laser. This apparently works better as 5 lasers are used to cover a bigger field of view.