An international team of researchers has announced the discovery of an Earth-sized exoplanet. Its orbit lies within the habitable zone of a red dwarf star.
The discovery was made in 2024 as a result of analyzing data collected by the TESS telescope. It managed to detect periodic changes in the brightness of the red dwarf GJ 12. They were caused by transits of the exoplanet GJ 12 b, whose radius is only 4% smaller than that of Earth, and whose equilibrium temperature is 26.85 °C, placing it right in the center of the system’s habitable zone.
To learn more about this world, the research team used the MAROON-X instrument. It is installed at the Gemini International Observatory and is designed to study Earth-like exoplanets around red dwarfs. MAROON-X uses the radial velocity method to estimate their mass and radius, as well as their orbital characteristics.
The results of observations show that the mass of GJ 12 b is 0.71 times that of our planet, and the eccentricity of its orbit is 0.16. For comparison, the eccentricity of Earth’s orbit is 0.0167, which is close to a circle. Next, knowing the mass of the exoplanet, researchers were able to estimate its density as approximately equal to or slightly less than that of Earth. Low density can be explained by the presence of volatile components on the planet (such as water mixed with the mantle), a low proportion of iron in the mass, or a combination of these factors.
According to scientists, the low mass of the exoplanet may also mean that it has a bloated atmosphere, which will be easily observable with the James Webb Telescope. At the same time, it may not be sufficient to maintain a full gas envelope unless it is regularly replenished by volcanic activity caused by tidal interactions with the red dwarf.
Researchers note another important factor. Compared to most typical red dwarfs, GJ 12 does not show any particular activity. This could play a positive role in preserving its atmosphere, increasing the chances of this world being habitable.
For more details on how red dwarf systems are conducive to life, read our article.
According to Phys.org
