US – NASA experts and San Diego State University detected exoplanet discovered outside the planet largest solar system within a system of two stars.

The discovery, made thanks to the Kepler space telescope, was announced at a conference of the American Astronomical Society.

This circumbinary exoplanet which orbits two stars is the size of Jupiter and was named Kepler-1647b. It also has the largest orbit for such planets where it revolves around these two stars in 1,107 days or a little more than three Earth years.

This is the eleventh circumbinary exoplanet discovered since 2005. These planets are sometimes called ‘Tatooines’, referring to the saga of “Star Wars”.

Kepler-1647b is 4,400 million years old and is in the constellation Cygnus, 3,700 (one light year equals 9,460 trillion kilometers) light years from Earth.

The great search continue

Scientists detect exoplanets when they pass in front of their stars, causing a temporary decrease in brightness. This technique, called astronomical transit; deduces the mass of the planet and the distance it is from its star.

“Finding circumbinary exoplanets is much more difficult,” said William Welsh, an astronomer at San Diego State University and one of the coauthors of this discovery. According to him the passage of the planet in front of the two stars is not evenly spaced and therefore its duration can vary.

Once a candidate exoplanet is discovered, astronomers use sophisticated computer programs to determine if indeed it is a planet, a process that can be long and arduous.

The astronomer Laurance Doyle of the SETI Institute and one of the coauthors had observed the transit of this planet for the first time in 2011. But there was no data collected and analyzed over several years to confirm that this astronomical transit was in fact a circumbinary exoplanet.

The planet Kepler-1647b is also distinguished because it is farther from its two stars that what are generally known circumbinary exoplanets.

In addition, Kepler-1647b is located at a distance that makes it habitable, neither too hot nor too cold, where water could exist in liquid form. Being a gaseous planet, it is unlikely to develop life but could emerge in any moons orbiting the planet.

Welsh concluded that in addition to its potential habitability, Kepler-1647b is important because it could point out the most frequent existence of a population of large circumbinary exoplanets orbit far from their stars.