A team of American astronomers from the University of Arizona, led by Michael Hart, has developed a technique that allowsobtain astronomical images from Earth as sharp as those captured with the Hubble Space Telescope, and also much faster. The technique, calledadaptive laser optics, was released today in the magazineNature.
Atmospheric turbulence distorts light from celestial objects that reaches the mirrors of a ground-based telescope. Specifically, “most of the distortion occurs less than half a mile above Earth, where heat alters air currents,” the scientists explain.
From his observatory on Mount Hopkins, Hart and his colleagues projected agreen color laser beam to the sky, which bounces off oxygen and nitrogen molecules in the upper atmosphere and “creates” 5 “artificial stars”. In this way it is possible to studywhat exactly is the effect of turbulence on the image of celestial objects. And, with the help of a computer, it can be? Canceled? the distortion caused by the atmosphere in a specific area of the field of view. “It is like seeing clearly only through a hole, although thanks to our technique this hole has become much larger”, clarifies Hart, who intends to studythe oldest galaxies in the Universe, as well assupermassive stars.
If all goes according to plan, it could be applied toGiant Magellan Telescope, the next largest telescope in the world, which is being built in Chile and will come into operation in 2018.
