(Kemmer et al., 2022)
The TESS space telescope has discovered a new hot super-Earth located in a red dwarf system very close to the Sun.
Further studies of this object can help astronomers understand the origin of the sub-Neptune desert, the lack of planets close to stars with masses of 1.4-2 Earth masses.
One of the problems in exoplanetology has become the nature of the sub-Neptune desert.
This is the name given to the observed lack of planets with masses of 1.4-2 Earth masses that are close to their stars, which separates super-Earths and mini-Neptunes.
It is still unclear exactly what mechanisms lead to the formation of these types of planets and why the desert phenomenon occurs.
Perhaps rocky super-Earths are born as a result of photoevaporation of the outer shells of mini-neptunes rich in hydrogen, or another mechanism for the loss of mass of the atmosphere.
To understand this, scientists need to increase the sample of known exoplanets of these types and determine their parameters with great accuracy.
A team of astronomers led by Jonas Kemmer from the University of Heidelberg announced the discovery of the exoplanet GJ 3929b in the M-dwarf system, located 51.6 light-years from the Sun.
Initially discovered by the TESS space telescope using the transit method, the discovery was subsequently confirmed using the CARMENES, SAINT-EX, LCOGT and OSN ground-based telescopes, which also helped to determine the parameters of the object.
The radius of the planet GJ 3929b was estimated at 1.15 Earth radii, and the mass at 1.21 Earth masses.
This gives a bulk density value of 4.4 grams per cubic centimeter, which is comparable to Earth's average density, so the object could be a rocky exoplanet.
A year on the planet lasts 2.61 Earth days, it is at an average distance from its star of about 0.0026 astronomical units.
The equilibrium temperature of GJ 3929b is estimated at 569 kelvin, which means that it belongs to the category of hot super-Earths.
The brightness of the parent star (which is one third smaller than our own) and the size of GJ 3929b make the exoplanet an interesting target for future research with the James Webb Space Telescope, which will be able to find its atmosphere, if there’s one.
In addition, there may be another exoplanet in the system with an orbital period of 14.303 days, however this has yet to be confirmed.
Sources:
arXiv.org: https://arxiv.org/abs/2202.00970
Phys.org: https://phys.org/news/2022-02-hot-earth-sized-exoplanet-tess.html