May 26, 2009

New Technique Could Find Another “Pale Blue Dot”

Written by Nancy Atkinson

By looking back at Earth from alien’s point of view, scientists have developed a new technique to look for other worlds that might harbor oceans, and therefore life.

Using the old Deep Impact spacecraft, which is now being used for the EPOXI mission, scientists are able to look at the spectrum of an extrasolar planet’s light which would reveal the presence of water.

“We used the High Resolution Imager telescope on Deep Impact to look at Earth from tens of millions of miles away,” said Nicolas B. Cowan, of the University of Washington, "and developed a method to indicate the presence of oceans by analyzing how Earth’s light changes as the planet rotates. This method can be used to identify extrasolar ocean-bearing Earths.”

Last year, the EPOXI science team was able to take videos of the Moon transiting Earth, (see our article from July 2008). The team has now practiced the technique by looking back at Earth, and have determined that they should be able to detect oceans on other worlds by looking at the changing spectrum of light the planet gives off as it rotates.

Full article here:

http://www.universetoday.com/2009/05/26/new-technique-could-find-another-pale-blue-dot/