They discover a superstierra in the habitable zone of a nearby red dwarf

The new planet, called GJ 3998 D, is the third planet found in this system, according to the IAC on Tuesday in a statement.

“GJ 3998 D is an incorporation welcome to the planetary census of our cosmic neighborhood,” according to Atanas Stefanov, a doctoral student and main author of the study, published in Astronomy & Astrophysics.

This Supertierra seems to be in the habitable zone of one of the stars closest to the sun.

“This gives us one more reason to continue looking for habitable planets around us,” Stefanov said.

The newly discovered planet, GJ 3998 D, It is a superstierra with a mass six times greater than that of the Earth, it is located in the “optimistic” habitable area of ​​its star and complete an orbit every 41.8 days.

At this distance, GJ 3998 D receives only 20 % more stellar radiation compared to what the Earth receives from the sun.

“GJ 3998 is significantly smaller and colder than the sun, which displaces the habitable area closer to the star,” said Alejandro Suárez Mascareño, a researcher at the IAC and co -author of the study.

“Although it is certainly different from the Earth, if the planet is rocky, it could be able to house liquid water on its surface, one of the main requirements for life,” said Jonay I. González Hernández, a researcher of the IAC and also co -author.

The proximity of this system to the Sun makes GJ 3998 D an attractive candidate for atmospheric characterization.

“It should be possible to verify the presence of an atmosphere and seek oxygen using the future Andes spectrograph in the extremely large telescope (elt) of ESO. GJ 3998 D would also be a good goal for the future Exo Life Finder (ELF) of 50 meters, led by the IAC, which will seek biomarkers in the exoplanet atmospheres ”, according to Rafael Rebolo, IAC researcher and co -author of the study.

The discovery is part of the Hades program, an international effort to explore planetary systems around red dwarfs through the Nazionale Galileo telescope (TNG) at the ROQUE DE LOS MUDO OBSERVATORY, on the Spanish island of La Palma, located in the Atlantic.

The red dwarfs are smaller and colder stars than the sun and constitute almost three quarters of the stellar population of our galaxy.

Their low mass and abundance make them priority objectives in the search for low -dough planets, and GJ 3998, one of these red dwarfs, has been of special interest to the community due to its proximity (59 light years) and its moderate star activity.

Thus, using the HARPS-N spectrograph in the TNG telescope, the equipment was able to detect small oscillations in the star movement, caused by the gravitational pull of the planets in orbit.

A previous study conducted in 2016 by the same team had already detected two planets, so that the presence of an additional signal in the data led to the continuation of the observations and the new analysis of the data set.

“With three known planets in the system, GJ 3998 stands out once again how common are multiplane systems. The planets, in particular those of low dough, are rarely alone: ​​they prefer to have a company. Often, when we return to study a system with new measurements and new methods, we found planets that had previously gone unnoticed, ”said Stefanov.

He has also participated in this discovery Nicola Nari, a doctoral student at the ULL.