This video says about itself:
The Laser Interferometer Gravitational Wave Observatory is spearheading the completely new field of gravitational wave astronomy and opening a whole new window on the universe.
LIGO’s exquisitely sensitive instruments may ultimately take us farther back in time than we’ve ever been, catching, perhaps, the first murmurs of the universe in formation.
From New Scientist in the USA:
Astronomers clash with US air force over laser rules
* 22:29 13 October 2009 by David Shiga
Could astronomers accidentally blind Earth-observing satellites? That seems to be the worry of the US air force, which restricts the use of lasers pointed at the sky to help focus telescopes. But some astronomers warn they will miss key observations under the rules, which have tightened in recent years.
The laser causes a layer of sodium atoms at an altitude of about 90 kilometres to glow, producing an artificial star whose twinkles reveal the turbulence. Shape-shifting mirrors on the telescopes, called adaptive optics, then correct for the blurring by adjusting their shape many times per second.
If such a laser were to hit the optics of an Earth-observing satellite, it could cause damage. So the air force’s Space Command has for years restricted when and where US observatories can fire them, and the observatories have voluntarily complied, with little impact on astronomy.
Then about two years ago, just as kinks in the laser technology were being ironed out and interest in the lasers was growing, the rules were tightened. Now astronomers say the restrictions are beginning to chafe, according to a story first reported by the American Physical Society.
“Significant negative impacts of these new restrictions on scientific productivity are being felt,” says a 2008 report … by the US Association of Universities for Research in Astronomy, which is based in Washington, DC.