New exoplanet nearly size of Earth discovered by James Webb telescope

Using the James Webb Space Telescope, scientists have confirmed the existence of the exoplanet LHS 475 b for the first time. The object located at a distance of 41 light years from the Earth is 95% of the volume of the Earth.

A science team at Johns Hopkins University's Applied Physics Laboratory, led by Kevin Stevenson and Jacob Lustig-Yaeger, first studied the exoplanet LHS 475 b with the TESS space telescope. The results of the study indicated that the scientists discovered a new planet, but to be sure of this, they decided to use the capabilities of James Webb as well.

The James Webb Near Infrared Spectrograph (NIRSpec) captured the exoplanet LHS 475 b in just two transit observations. Lustig-Yaeger said that there is no doubt that the planet exists, because preliminary data from the telescope confirms it.  Kevin Stevenson, in turn, noted that they were impressed by the fact that LHS 475 b is a rocky planet.

According to Mark Clampin, director of the astrophysics division at NASA headquarters in Washington, the first results of observations of LHS 475 b open up many other opportunities for studying the exoplanet's atmosphere with James Webb. He said that the space telescope brings scientists even closer to understanding the terrestrial worlds outside the solar system in a new way.

According to NASA, of all the telescopes in operation, only the James Webb is able to present the atmospheric characteristics of Earth-sized exoplanets. The team of scientists tried to estimate the composition of the gas mantle of LHS 475 b by analyzing it using transmission spectroscopy. It is currently unknown whether the exoplanet has an atmosphere.

Erin May of Johns Hopkins University's Applied Physics Laboratory said the James Webb telescope is so sensitive that it can easily detect a variety of molecules, but astronomers still cannot draw any definitive conclusions about LHS 475 b's atmosphere. And according to Lustig, the exoplanet cannot have such a thick atmosphere dominated by methane, as is the case with Saturn's moon Titan.

Data from James Webb also showed that LHS 475 b is several hundred degrees hotter than Earth.  If scientists find clouds above the planet, it will have something in common with Venus, which has a carbon dioxide atmosphere.

LHS 475 b orbits the red dwarf exoplanet LHS 475 in two days.  LHS 475 b is closer to its star than any other planet in the solar system.