On Thu, Aug 09, 2001 at 02:45:01PM +0100, Andrew Nemchenko wrote: > I've seen scientists use a high powered laser to burn a hole in the > atmosphere and then look through the microscope throught that > hole. Since there is no atmosphere there is not light refraction, > therefore they were able to see stars and planets very clearly with > out any twinkle to them. That's not what they're doing - see http://antwrp.gsfc.nasa.gov/apod/ap010425.html (the NASA Astronomy Picture of the day for 25 April 2001) for a neat related picture. Basically, they know what the laser should look like in the atmosphere, and they can use adaptive optics to make the laser look "right", thereby eliminating (or at least reducing) the atmospheric blurring. -- Scott Raun sraun at fireopal.org