New Super-Earth Planet Discovered in Habitable Zone of Nearby Star

A new super-Earth was just discovered circling a star called GJ 625 that's only 21 light-years away.

According to a report from Phys Org, GJ 625 is an M-dwarf star about a third of the size and mass of the sun. The newly discovered planet, GJ 625, has a minimum mass of 2.8 Earth masses, making it the lightest exoplanet ever found orbiting an M2 star. It's found orbiting the inner edge of the star's habitable zone.

"As GJ625 is a relatively cool star the planet is situated at the edge of its habitability zone, in which liquid water can exist on its surface," Canary Islands Institute of Astrophysics' Alejandro Suárez Mascareño explained in an official statement from the Instituto de Astrofísica de Canarias (IAC). "In fact, depending on the cloud cover of its atmosphere and on its rotation, it could potentially be habitable."

Exoplanets classified as super-Earths are those that are bigger than Earth but smaller than Neptune.

A team of astronomers led by Mascareño began a series of studies on the star in 2013 that was completed over three and a half years.

They used the High Accuracy Radial velocity Planet Searcher for the Northern hemisphere (HARPS-N) spectrograph at the Telescopio Nazionale Galileo at the Roque de los Muchachos Observatory in Spain. With the analysis of 151 radial-velocity time series from HARPS-N, the researchers were able to discover the new super-Earth.

"In the future new observing campaigns of photometric observations will be essential to try to detect the transit of this planet across its star, given its proximity to the sun," Jonay González Hernández said. "There is a possibility that there are more rocky planets around GJ625 in orbits which are nearer to, or further away from the star, and within the habitability zone, which we will keep on combing."

The study was accepted for publication in the journal Astronomy and Astrophysics. It can also be accessed online on arXiv.