Wednesday, May 4, 2016

Three new Earth-sized planets discovered

Have scientists found an Earth 2.0 ? Image Credit: CC BY-SA 3.0 Luciano Mendez

Astronomers have identified three new terrestrial worlds around a relatively close 'ultracool' star.
The hunt for a habitable planet outside our solar system has received a substantial boost this week thanks to the discovery of three temperate Earth-sized worlds in orbit around a star that, despite being relatively close, is so dim that it is not even possible to see it without the use of a telescope.

Extrasolar planets are typically identified by observing them transiting in front of their parent star, a technique that can also be used to determine their size and orbital distance.

This method can also potentially reveal information about a planet's atmosphere, but because the parent star in most cases is extremely bright it is usually impossible to make anything out.

Now though, by identifying planets around extremely cool and dim stars, astronomers are hoping to get around this problem and to observe the atmospheres of extrasolar worlds directly.

This latest discovery, which was made around an ultracool star 39 light years away, features one planet in particular out of the three that appears to be a prime candidate for further study.

When the James Webb Space Telescope arrives in 2018 it should even be possible to observe the atmospheres of these worlds and find out if anything might be living there.

"Systems around these tiny stars are the only places where we can detect life on an Earth-sized exoplanet with our current technology," said study lead author Michael Gillon.

"So if we want to find life elsewhere in the universe, this is where we should start to look."