40 light years away: Gliese 12 b, an Earth-like exoplanet, found in the constellation of Pisces

An international team of scientists, with Spanish participation, has discovered an exoplanet the size of Earth or Venus 40 light years away, in the constellation of Pisces. Called Gliese 12 b, this planet orbits a cool red dwarf and is located in the habitable zone of its star., making it a promising target for the James Webb Space Telescope to study its atmosphere.

A promising discovery

Gliese 12 b, a newly discovered exoplanet 40 light years from Earth, has captured the attention of the scientific community. This planet, intermediate in size between Earth and Venus, orbits a cold red dwarf in the constellation of Pisces. The research, which involves the participation of the Instituto de Astrofísica de Canarias (IAC) and the Centro de Astrobiología (CAB, INTA-CSIC), has revealed that Gliese 12 b is located in the habitable zone of its star, making it an ideal candidate to study its atmosphere with the James Webb Space Telescope.

The discovery was made by combining data from space and ground-based telescopes, including NASA's TESS satellite, CARMENES at the Calar Alto Observatory, and MuSCAT2 on the Carlos Sánchez Telescope at the Teide Observatory. This temperate planet is the closest one detected so far using the transit method, which observes periodic dimmings. of a star caused by the passage of the planet in front of it.

Living conditions

Red dwarfs, such as the one orbiting Gliese 12 b, They emit less energy than stars like the Sun, which means that their habitable zones are closer to them.This makes it easier to detect transiting planets within these zones. The estimated surface temperature of Gliese 12 b is about 42 °C, although its final temperature will depend on whether it has been able to retain an atmosphere and on the composition of this atmosphere.

Gliese 12b It orbits its star every 12,8 days at a distance that is only 7% of the distance between the Earth and the Sun.Despite this proximity, the host star, Gliese 12, is relatively small, at just 27% the size of the Sun and 60% of its surface temperature. This means that Gliese 12 b receives 1,6 times more energy than Earth, which could significantly influence its habitability conditions.

Comparison with Venus and potential for further studies

The exoplanet Gliese 12 b has been compared to Venus due to its size and the energy it receives from its star. "Although we don't yet know if Gliese 12 b has an atmosphere, we've been thinking of it as an 'exovenus'", with a size and energy received from its star similar to that of our planetary neighbor in the Solar System," says Masayuki Kuzuhara, associate professor at the Tokyo Center for Astrobiology.

The comparison between Gliese 12 and Venus can provide valuable insights into the atmospheric evolution and habitability conditions of terrestrial planets.Earth and Venus are very similar planets in size and mass, but their histories have been very different."Gliese 12 b's atmosphere could teach us a lot about how atmospheric evolution and habitability conditions change on terrestrial planets as they evolve," explains Enric Pallé of the IAC.

An ideal candidate for the James Webb telescope

Gliese 12 b's host star, a red dwarf, shows no signs of extreme behavior, making it an ideal candidate for studying its atmosphere with the James Webb Space Telescope. Thanks to current technology, it is possible to use the transit method to analyze the chemical composition of exoplanetary atmospheres., identifying the molecules present and better understanding their composition.

"To date, we only know of a handful of systems that are close enough to us to meet other criteria needed for this type of study, called transmission spectroscopy," said Michael McElwain, an astrophysicist at NASA's Goddard Space Flight Center. To better understand the diversity of atmospheres around temperate Earth-like planets, more examples like Gliese 12 b are needed.

The discovery of Gliese 12 b Not only does it expand our knowledge of exoplanets, but it also opens up new possibilities for studying habitability. and the atmospheric evolution of planets in our galaxy. With the help of the James Webb Telescope, scientists hope to unravel more secrets of this fascinating exoplanet and advance our understanding of the universe.