They find 2 potentially habitable planets orbiting a star close to the Sun

Two planets with masses similar to Earth’s have been discovered by an international scientific team. These worlds orbit in the habitable zone of the red dwarf. GJ 1002one of the closest stars to our solar system.

“Nature seems determined to show us that terrestrial planets are very common. With these two, we already know of seven in planetary systems very close to the Sun,” Alejandro Suárez, a researcher at the Instituto de Astrofísica de Canarias (IAC) and lead author of the study accepted for publication in Astronomy & Astrophysics, explained in a statement on Thursday.

The new exoplanets (worlds that are not part of our solar system) and their host star are located at a distance of less than 16 light-years from the Sun.

habitable zone of a cold star

The IAC notes that GJ 1002 b, the inner planet, takes just over 10 days to complete one orbit of its star; while GJ 1002 c, for its part, needs a little more than 21 days.

GJ 1002 is a red dwarf with just one eighth the mass of the Sun and is quite cold and weak, which means that its habitable zone is very close to the star, indicated Vera María Passegger, co-author of the article and IAC researcher. .

If both exoplanets were in our solar system, they would be located between Earth and Mars. Image: Alejandro Suárez / IAC / NASA

The star’s closeness to the solar system makes the two planets, especially GJ 1002 c, excellent candidates for characterizing their atmospheres on the basis of light reflection or thermal emission, the astrophysics institute added.

“The future ANDES spectrograph for the ESO ELT telescope, in which the IAC participates, will be able to study the presence of oxygen in the atmosphere of GJ 1002 c”, explained Jonay González, IAC researcher and co-author of the work.

Both worlds also meet all the characteristics to become objectives of the future LIFE space mission, currently under study.

international collaboration

The discovery has been possible thanks to a collaboration between the teams that operate the ESPRESSO instruments, installed on the VLT telescope of the European Southern Observatory in Chile; and CARMENES, from the Calar Alto observatory in Spain; who viewed GJ 1002 between 2017 and 2021.

“Due to its low temperature, the visible light of GJ 1002 is too dim to measure its variations in radial velocity with most spectrographs,” said Ignasi Ribas, a researcher at the Institute of Space Sciences (ICE-CSIC) and director of the Institute. d’Estudis Espacials de Catalunya (IEEC).

CARMENES has a sensitivity to a wide range of wavelengths in the near infrared, superior to that of other spectrographs dedicated to detecting speed variations in the movement of stars, which allowed GJ 1002 to be studied from the 3.5-meter telescope of Calar Alto.

The combination of ESPRESSO and the light-gathering power of the 8-meter-diameter VLT telescope made it possible to obtain measurements with a precision of just 30 cm/s, unattainable by almost any other instrument in the world.

“Either of the two groups would have had a lot of difficulties if they had tackled this work independently. Together we were able to go much further than we would have done separately,” said Alejandro Suárez.

Researchers Rafael Rebolo López, Víctor Sánchez Béjar and Enric Pallé have also collaborated on this publication from the IAC.

The stellar astrophysics and exoplanets group of the Complutense University of the Faculty of Physical Sciences and the Institute of Particle Physics and the Cosmos of the Complutense University of Madrid (IPARCOS-UCM), whose researcher David Montes is also involved in the discovery. the institutional representative of the center in the CARMENES international consortium.

With information from EFE