An international scientific team led by researchers from the Instituto de Astrofísica de Canarias (IAC) has discovered two Earth-sized planets orbiting a red dwarf star GJ 1002. The star is less than 16 light-years from the solar system and is cool and weak. has one-eighth the mass of the sun.
The two planets – GJ 1002b and GJ 1002c – have masses similar to Earth’s. They are in the habitability zone of their star. The planet GJ 1002b takes just over 10 days to orbit the star, while GJ 1002c takes just over 21 days.
The proximity of this system to our solar system indicates that the planets are good candidates for studying their atmospheres based on their reflected light or their thermal emission.
Jonay I. González Hernández, an IAC researcher and co-author of the paper, said: “The future ANDES spectrograph for the ELT telescope at ESO, in which the IAC participates, could study the presence of oxygen in the atmosphere of GJ 1002c. In addition, both planets meet the characteristics necessary to be targets for the future LIFE mission, which is currently in a study phase.”
The CARMENES observed the star between 2017 and 2019, while ESPRESSO observed it between 2019 and 2021.
Because the star has a low temperature, the visible light from the star is too weak to measure the variations in velocity with most spectrographs. But CARMENES’ high sensitivity over a wide range of near-infrared wavelengths allowed the team to study GJ 1002 from the 3.5m telescope at the Calar Alto Observatory.
Alejandro Suárez Mascareño, an IAC researcher, said: “Nature seems eager to show us that Earth-like planets are quite common. With these two, we now know 7 in planetary systems quite close to the sun.
- A. Suárez Mascareño, E. González-Alvarez et al. Two temperate-mass planets orbiting nearby star GJ 1002. Astronomy and Astrophysics. DOI: 10.1051/0004-6361/202244991