LHS 475 b is the first exoplanet, the existence of which was confirmed by the Webb telescope. It is located 41 light years from us in the constellation Octantus, and its dimensions are almost the same as those of the Earth.
A team of astronomers from Johns Hopkins University’s Applied Physics Laboratory, led by Kevin Stevenson and Jacob Lustig-Yager, first spotted signs of a candidate exoplanet in data from NASA’s Transiting Exoplanet Survey Satellite (TESS). However, it was the Webb Near-Infrared Spectrograph (NIRSpec) that confirmed its existence by observing two transits of LHS 475 b in front of its parent star.
“There is no doubt that the planet exists. Webb’s first data confirm this,” said Lustig-Yager in a NASA press release.
According to the space agency, among the telescopes in operation today (both ground-based and orbiting), only Webb has the necessary permission to accurately characterize the atmospheres of exoplanets the size of Earth (the diameter of LHS 475 b is 99% of the diameter of our planet). The research team is still working to determine what atmosphere is on top of the rock mass using analysis of its transmission spectrum.
There are some Earth-type atmospheres that we can rule out. It cannot have a thick methane-dominated atmosphere like that of Saturn’s moon Titan,” Lustig-Jaeger explained.
The team also notes that while the planet may not have an atmosphere, there are some components that have not been ruled out, such as an atmosphere of pure carbon dioxide.
“Contrary to common sense, an atmosphere consisting of 100% carbon dioxide is so compact that it is very difficult to detect,” Lustig-Jaeger said.
The researchers also confirmed that the planet orbits in just two days, information that was revealed almost instantly by the accurate Webb light curve. Although LHS 475 b is closer to its star than any other planet in our solar system, the temperature of its red dwarf is less than half that of the Sun. That is why researchers hope that the exoplanet may still have an atmosphere.
James Webb took a detailed look at the atmosphere of the exoplanet WASP-39b, located 700 light years from Earth.
Source: NASA, Engadget
- The James Webb Telescope was launched into space in December 2021, and in mid-January 2022 reached a working halo orbit around the second Lagrange point in the Sun-Earth system, and in July, after several months of instrument calibration and optical adjustment, it finally went live of his scientific program.
- James Webb’s first targets included exoplanet atmospheres, protoscopies, circumstellar disks, quasars, trans-Neptunian objects, and comets. In September 2022, the telescope received images of the first exoplanet – HIP 65426b, a giant planet believed to be several times the mass of Jupiter, the largest planet in the Solar System.
- In total, Webb spent almost a year in space – here’s a selection of all his most amazing pictures so far.
