Looking for life in the rainbow leg

Rainbow may be an important key to identifying habitable planets, a researcher claims. He said scattered light could reveal the presence of liquid water.

Assistant Professor Jeremy Bailey from the Center for Astrophysics at Macquarie University, Australia, said understanding how light scatters from liquid droplets on a planet's atmosphere could be an indicator. Sensitive about water vapor in its clouds.

Bailey introduced the idea of ​​using light polarization (a feature that helps create rainbow) to find liquid water in the latest issue of Astronomical Journal.

"The rainbow is born when light hits a drop of water scattered at a particular angle," he said. "This angle depends on the refractive index of the liquid, so for different types of liquids that exist in the clouds of other planets, we will see rainbows at different angles."

"That's a way to help us determine that Venus's clouds are droplets of concentrated sulfuric acid."

Because each type of liquid has its own scattering properties, Bailey thinks astronomers can use this method to detect water vapor in certain planet's atmosphere. Techniques can be used in parallel with the use of optical spectroscopy.

T. An