James Webb discovered his first exoplanet. The new exoplanet Webb is just 99% the diameter of Earth. NASA announced the discovery on its website Wednesday, saying the planet is now classified as LHS 475b and was found closer to its star than any planet in our solar system. As a result, it completes an orbit in just two days.
That’s not all, Webb also observed that the planet is a few hundred degrees warmer than ours, and that it looks more like Venus than Earth. The Earth, as we all know, is habitable and contains an atmosphere ripe for life to exist. Venus, however, is covered in thick clouds and its atmosphere is full of carbon dioxide.
At this time, it’s unclear exactly what the atmosphere of Webb’s first exoplanet is made up of or if it even has one. However, there are plans to go deeper into this information somewhere. NASA says researchers ran a transmission spectrum on the planet, but it was unclear whether or not an atmosphere existed there.
What we have ruled out, however, is that it cannot have a thick methane-dominated atmosphere like that found on Titan. Because they have such a hard time figuring out exactly what type of atmosphere there is, it’s possible they don’t have one, or it’s a 100% carbon dioxide atmosphere , as they are much more compact and harder to detect.
While Webb’s first exoplanet is closer to its star than any planet in our solar system, the red dwarf at the center of the system is also much cooler than our Sun. As such, it’s likely the planet could still be cold enough to have an atmosphere.
Additionally, Webb’s discovery of exoplanets showed that red dwarf stars can have Earth-like planets orbiting them, which could make it easier to detect Earth-like planets if we start looking around. red dwarf stars like the one found in LHS 475. Webb has detected atmospheres on exoplanets before, so we may see more developments from that in the future.