If there's life on other planets, astronomers at the University of Arizona say they've found a better way to view it.
At the Center for Astronomical Adaptive Optics in Arizona, astronomers have demonstrated for the first time that they can look at planets orbiting extrasolar stars, a feat that even the Hubble Space Telescope hasn't been able to accomplish.
Stars are millions of times brighter than planets, causing glare so bright it washes out the view for astronomers trying to observe planets in other solar systems. Now Phil Hinz, a graduate student in astronomy at the University of Arizona, has found a solution. His research is documented in a paper published this week in Nature.
"To look at the planet you need to get rid of the starlight," Hinz said. "If you have two telescopes looking at the star there are waves of light going in from each telescope, and if you can get the waves of light to interfere ... and the peaks of one wave line up with the trough of another wave train of light, [the waves] cancel each other out. We built our system that way."
Previously, astronomers could only predict that other planets were orbiting stars by measuring the "wobble," or the gravitational movement, of the star. This method has been somewhat effective in identifying new planets, but astronomers hope that now planets even further out in space can be identified.
"The first planet outside our solar system wasn�t found until 1995," Hinz said. "There are only 15 known planets outside our solar system. It�s an ongoing search."
The astronomers at CAAO used the Multiple Mirror Telescope and a technology called "nulling interferometry" to block the light of the red star Betelgeuse -- a supergiant star in the nearby Orion constellation -- to reveal the dust cloud revolving around it. Hinz said 100 other stars in the 30 light year range -- and as many solar systems �- can now be studied.
Nick Woolf, an astronomer at the University's Steward Observatory, said, "If you can look at planets around other stars and actually see them, you can analyze the glow coming from them. And by observing certain things in that atmosphere, you would indeed know if life was developed there."
The Large Binocular Telescope under construction on Mt. Graham, Arizona, will be used next to search for planets the size of Jupiter and larger. Although scientists don�t expect to find life on such planets, since they�re mostly gaseous, they can indicate which stars have planetary systems.
