“Gliese 12b is one of the top targets” – Life may be possible on an exoplanet

The exoplanet Gliese 12b is one of the few planets on which life could be possible. Further investigation should reveal details.

TOKYO – More than 5,000 planets outside our solar system – so-called exoplanets – have been discovered so far. Many of them are interesting to research because, for example, they have the consistency of cotton candy or have other properties that are difficult to imagine. But research rarely finds a planet on which life might be possible. But thanks to the TESS space telescope of the American space agency NASA, such a discovery has now been made.

Liquid water and life may be possible on the exoplanet Gliese 12b

The exoplanet Gliese 12b orbits a red dwarf star located about 40 light-years away in the constellation Pisces. It is about the same size as Earth – or slightly smaller – compared to Venus. “We have found the closest temperate Earth-sized world,” says Masayuki Kuzuhara of the Astrobiology Center in Tokyo, who led a study on Gliese 12b. “Although we don't yet know if it has an atmosphere, we considered it to be an exoplanet of Venus, with the same size and energy input from its star as our planetary neighbor in the solar system.”

What is particularly interesting for the research is the fact that the exoplanet's surface temperature is estimated to be around 42 degrees Celsius (without an atmosphere). This means that the presence of liquid water is possible on the surface of Gliese 12b, which is an important prerequisite for the possible existence of life on this planet. Further observations with the James Webb Space Telescope could show whether or not Gliese 12b has an atmosphere. The atmosphere is a double-edged sword: it maintains conditions favorable for life on Earth, while the runaway greenhouse effect has turned Venus into a hellish planet.

Can Earth-sized planets orbiting red dwarf stars retain their atmospheres?

“Gliese 12b is one of the best targets to study whether Earth-sized planets orbiting cool stars can retain their atmospheres,” says Shishir Dholakia, a doctoral student at the Center for Astrophysics at the University of Southern Queensland in Australia. He led a second research team that also examined the newly discovered exoplanet. Both research teams believe that the exoplanet Gliese 12b could help unravel some aspects of the evolution of our solar system.

“The first atmosphere of Earth and Venus is thought to have been eroded and then replenished by the release of volcanic outgassing and the bombardment of remaining material in the solar system,” explains Larissa Palethorpe, who participated in the study. In the specialized magazine Monthly Notices of the Royal Astronomical Society published had become. “Earth is habitable, but Venus is not because it no longer has water. Since Gliese 12 b is between Earth and Venus in terms of temperature, its atmosphere can teach us a lot about the habitability trajectories of planets as they evolve.”

“We know of only a few temperate Earth-like planets.”

The study was conducted by research leader Kuzuhara and his team In the specialized magazine Astrophysical Journal Letters published. Co-author Michael McElwain emphasizes the importance of the exoplanet Gliese 12b: “We know of only a few temperate Earth-like planets that are close enough to us and meet the other criteria required for this type of study, called transmission spectroscopy.” He continues: “To better understand the diversity of atmospheres and evolutionary consequences of these planets, we need more examples like Gliese 12b.” (unpaid bill)