Article Posted on : - Nov 03, 2010

WASHINGTON (BNS): According to a new study, astronomers have found that a planet's "true colours" can reveal important details. Planets around other stars probably exhibit a rainbow of colours every bit as diverse as those in our solar system.

In near future, astronomers will harness colour to learn more about exoplanets. Earth, in particular, stands out clearly among the planets, like a blue jay in a flock of seagulls.

According to NASA astronomer Lucy McFadden and UCLA graduate student Carolyn Crow, a simple way to distinguish between the planets of our solar system is based on colour information.

"The method we developed separates the planets out. It makes Earth look unique," Crow said.

This suggests that someday, when we have the technology to gather light from individual exoplanets, astronomers could use colour information to identify earth-like worlds.

"Eventually, as telescopes get bigger, there will be the light-gathering power to look at the colors of planets around other stars. Their colors will tell us which ones to study in more detail,” McFadden said.

NASA's Deep Impact spacecraft has brought the new colour information about Earth, the moon and Mars.

As Deep Impact cruised through space, its High Resolution Instrument (HRI) measured the intensity of Earth's light. HRI is an 11.8-inch (30 cm) telescope that feeds light through seven different colour filters mounted on a revolving wheel. Each filter samples the incoming light at a different portion of the visible-light spectrum, from ultraviolet and blue to red and near-infrared.

The colour concept will determine Earth’s layout in front of alien astronomers and it will also figure out how to spot earthlike worlds around other stars.