JWST has just confirmed its first exoplanet, the size of Earth: ScienceAlert

Since its launch in December 2021, the James Webb Space Telescope (JWST) has been operating Records have been broken.

Now the instrument has spotted its first planet around a star other than our own, and With a diameter estimated at about 99 percent of the Earth’s diameter It looks somewhat familiar.

Observations from the NASA Transiting Exoplanet Survey Satellite (he-goat) indicated that the planet existed, but now high-resolution images provided by the Near Infrared Spectrometer (NIRSpec) aboard JWST have confirmed it.

Despite the similar size, the planet is thought to be much hotter than our home world, orbiting a red dwarf star close enough to complete its orbit in just a couple of days.

“There is no doubt that the planet exists,” says astronomer Jacob Lustig-Yegerfrom the Applied Physics Laboratory at Johns Hopkins University in Maryland. Webb’s original data proved correct.

Named LHS 475 b, this newly discovered object lies 41 light-years away in the constellation Octane. As with other exoplanets, it was spotted by looking at the shadow produced as it passed in front of its star.

What makes JWST special is that it can be looked at transmission spectrum; The variety of wavelengths of light filtered around the planet that can reveal the qualities of its atmosphere.

Right now, we don’t have enough data to tell us what type of atmosphere LHS 475 b has, if it has atmosphere at all. So far, astronomers are confident that it lacks a thick, methane-rich atmosphere, like the one that surrounds Saturn’s moon. Titan.

“The telescope is so sensitive and the data so accurate that we could have easily detected many different molecules, but we don’t see much yet,” he said. says astrophysicist Ortiz Ceballosof the Harvard-Smithsonian Center for Astrophysics in Massachusetts.

But they cannot rule out the presence of a shallow atmosphere consisting of pure carbon dioxide.

The extra resolution offered by JWST means researchers can search for much smaller stars and planets. Usually, telescopes search for exoplanets larger than Jupiterabout 11 times larger than Earth.

Information is also being gathered at a rapid pace: it only took two transits (or passes in front of its star) for the JWST to identify LHS 475 b and some of its characteristics. Further reading should tell us more about what we’re dealing with here.

We’re also seeing JWST produce some quite the same Stunning photos from deep space, thanks to the sensitivity of the instruments on board — and it’s been going for just over a year. There is a lot more to come.

“These first observational results from a rocky Earth-sized planet open the door to many future possibilities for studying the atmosphere of the rocky planet using Webb,” Mark Clampin saysdirector of the Astrophysics Division at NASA Headquarters in Washington, D.C.

“Webb is bringing us closer and closer to a new understanding of Earth-like worlds beyond our solar system, and the mission is still in its infancy.”

The results were presented at a meeting American Astronomical Society On Wednesday, January 11, 2023.