A super earth It is a planet like ours, but much larger and more massive. These objects are the subject of study and Granada has participated in an international team, led by the astrophysicist Jose Antonio Caballerowhich managed to carry out the most detailed study of a structure of this type in the whole world to date.

gentleman, of CSIC-INTA Astrobiology Centerhas led a group that has had the collaboration of the Institute of Astrophysics of Andalusia and that has managed to model the interior of the exoplanet Gliese 486 b. This study has estimated the relative sizes of its metallic core and rocky mantle. “This is the first time that such a detailed study of the possible internal structure of an exoplanet has been carried out,” said Pedro Amado, a researcher at the IAA-CSIC and one of the authors of the work, which is published in the magazine Astronomy & Astrophysics. This analysis has been possible thanks to the data obtained with instruments such as Chara, Cheops, Hubble Space Telescope, Maroon-X, Tess and Carmenes. The team has also made predictions about the composition of the planet’s atmosphere and its detectability with the James Webb Space Telescope, which will soon point its segmented mirror at the planetary system.

Precisely, Gliese 486 b was discovered by the German-Spanish consortium Carmenes in 2021 thanks to the spectrograph of the same name located in the 3.5-meter telescope of the Calar Alto Observatory, in the Sierra de los Filabres in Almería. This planet, orbiting a red dwarf star just 26 light-years away, can now be considered the best-studied rocky planet outside our Solar System. “This exhaustive characterization has been carried out thanks to a wide range of instruments and telescopes located both on the ground and in space, including data in high resolution spectroscopy obtained with the carmen instrument from the Calar Alto Observatory and photometric data obtained with the telescopes of the Sierra Nevada Observatory”, points out Eloy Rodriguez, another of the authors of the work and a researcher at the IAA-CSIC. For Caballero, “Gliese 486 b has become the Rosetta Stone of exoplanetology: in the Solar System, we have the telluric planets Mercury, Venus, Earth and Mars. Now the fifth best-studied terrestrial planet in the Universe is Gliese 486 b.”

“Probably the most important results behind our work are not the values ​​themselves, but the opportunities they offer for further study,” he says. Esther González-Álvarez, CAB astronomer and another of the signatories of the article. González-Álvarez refers to future studies, such as the formation of planetary magnetic fields in the outer zone of the nucleus with liquid metals, since Gliese 486 b seems to have one like our Earth. These magnetic fields can act as a shield against storms originating from the stellar host and prevent erosion of the atmosphere. Due to its precise and exact characterization, Gliese 486 b may become the first (and only, for the moment) exoplanet where we can propose this future research.

The first exoplanet around a star similar to our Sun, 51 Pegasi b, was discovered in 1995. Since then, every year since then, the astronomical community discovers exoplanets that are less and less massive, closer and closer, and more and more similar to Earth. For Pedro Amado “the combination of data from space missions and ground instrumentation such as Carmen is It is shown as an exceptional way to characterize more and better the rocky exoplanets and to be able to compare them with those of the solar system”.