Though they don’t orbit around our sun, sub-Neptunes are the most common type of exoplanet, or planet outside our solar system, that have been observed in our galaxy. These small, gassy planets are shrouded in mystery…and often, a lot of haze. Now, by observing exoplanet TOI-421 b, NASA’s James Webb Space Telescope is helping scientists understand sub-Neptunes in a way that was not possible prior to the telescope’s launch.