Astronomers have announced the discovery of a new rocky exoplanet. It orbits a star relatively close to the Sun.
The discovery was made thanks to the Transiting Exoplanet Survey Satellite (TESS). It tracks 200,000 of the brightest stars closest to the Sun in search of fluctuations in brightness caused by exoplanet transits.
Such fluctuations were detected in the star TOI-1846. It is a red dwarf located about 154 light-years from the Sun. Subsequent ground-based photometric and spectroscopic observations confirmed the planetary nature of this signal.
Observations have shown that the exoplanet, designated TOI-1846 b, has a radius of about 1.792 times that of Earth and is 4.4 times more massive than it. This gives a density of 4.2 g/cm³. Thus, it is a rocky body. As for the parent star TOI-1846, its radius is approximately 0.4 times that of the Sun, and its mass is approximately 0.42 times that of the Sun. The effective temperature of the star is 3295 °C K, and its age is estimated at 7.2 billion years.
TOI-1846 b orbits the red dwarf once every 3.93 days, at a distance of approximately 0.036 AU (5.4 million km) from it. Despite its extreme proximity to the Solar System, the equilibrium temperature of TOI-1846 b is estimated at 295 °C, which is significantly lower than the surface temperature of Mercury. This is because red dwarfs emit much less energy than stars like our Sun.
Based on the parameters obtained, astronomers have concluded that TOI-1846 b is likely a water-rich super-Earth belonging to the so-called sub-Neptune desert, also known as the Fulton gap. These terms are used to explain the “deficit” of short-period (orbital period less than 100 days) exoplanets with a radius of about 1.5–2 times that of Earth. The most likely explanation for this is the loss of the primary atmosphere due to photoevaporation under the influence of high-energy radiation from the star.
Earlier, we reported on a rocky exoplanet found in the habitable zone around another red dwarf close to the Sun.
According to Phys.org
