Using the radial velocity (RV) method, an international team of astronomers has discovered two new exoplanets passing through a nearby M dwarf star known as GJ 1002. The newly discovered alien worlds have a mass similar to that of our planet and orbit their host star. The enclave Discovery reported in a published article. Astronomy and Astrophysics.

The Radial Velocity (RV) method for exoplanet detection relies on detecting fluctuations in the velocity of the central star due to the change in gravitational direction from an invisible exoplanet as the star orbits it. Thanks to this technique, more than 600 exoplanets have been discovered today.

Now, a team of astronomers led by Alejandro Suárez Mascareño of the University of La Laguna, Spain, has reported the discovery of two new extrasolar planets as a result of RV measurements of the M-dwarf GJ 1002. Observations were made that led to the discovery. Echelle Spectrograph for Rocky Exoplanets and Stable Spectroscopic Observations (ESPRESSO) and Exoearths with Near Infrared and Optical Échelle Spectrographs (CARMENES) and Calar Alto high resolution search for M-dwarfs.

“We investigated the nearby M-dwarf GJ 1002 using RV and activity indicators from ESPRESSO and CARMENES. Using a common model combining information with FWHM [повної ширини напівмаксимуму] CCF [крос-кореляційної функції] and in a multi-series Gaussian process RV, we found the presence of two planetary signals,” the researchers explained.

The newly discovered exoplanets were named GJ 1002 b and GJ 1002 c. Both planets orbit GJ 1002 within its habitable zone, and given that the star is only 15.78 light-years from Earth, the planets are among the closest planets to Earth with potentially habitable environments.

According to the article, the minimum mass of GJ 1002 b is about 1.08 Earth masses. It orbits its parent star at a distance of about 0.0457 AU every 10.35 days. The equilibrium temperature of the planet is estimated to be 230.9 K.

GJ 1002 c appears to be slightly larger than GJ 1002 b, as its minimum mass is calculated to be 1.36 Earth masses. The outer planet is separated from its host by about 0.074 AU and has an orbital period of 21.2 days. The equilibrium temperature of the GJ 1002 C is 181.7 K. The astronomers added that this alien world could be a good candidate for further atmospheric characterization.

The main star GJ 1002 is a faint M-dwarf of spectral type M5.5V. It has a radius of about 0.137 solar radii and a mass of about 0.12 solar masses. The effective temperature of the star is 3024 K and its metallicity has been measured as -0.25. The researchers noted that there could be additional Earth-mass planets in the outer half of GJ 1002’s habitable zone.