the blurring effect of the earth’s atmosphere is in large part the reason the hubble space telescope is well, a space telescope. land based telescopes have had to rely on a technology known as adaptive optics in which a reference star is used as a point of reference to adjust for the rivers of air they must see through to observe the heavens beyond.

the drawback to this is the relative shortage of good reference stars in the skies — in particular over the southern hemisphere.

enter the good folks of european souther observatory over at paranal observatory in chile — they have developed a new technique by which they create their own reference star using lasers.

“The Laser Guide Star System installed at Paranal uses the PARSEC dye laser developed by MPE-Garching and MPIA-Heidelberg. The laser beam takes advantage of the layer of sodium atoms that is present in Earth’s atmosphere at an altitude of 90 kilometres. Shining at a well-defined wavelength the laser makes it glow. Despite this star being about 20 times fainter than the faintest star that can be seen with the unaided eye, it is bright enough for the adaptive optics to measure and correct the atmosphere’s blurring effect. “

Full article at ESO here
Full adaptation from Science Daily here

» You can leave a comment, or trackback from your own site.