The James Webb Space Telescope (JWST) has made history by discovering its first exoplanet, named TWA 7b.
This small, distant world was directly imaged by JWST – a major milestone since the telescope became active in 2022. Unlike previous studies that observed known planets, this discovery marks the first time Webb has captured an unknown world on its own.
TWA 7b is located around 100 light-years from Earth in the constellation Hydrus.
The star it orbits is just 6.4 million years old and is surrounded by a large disc of gas and dust – a perfect environment for new planets to form. Webb used its MIRI instrument and a special device called a coronagraph to block out the star’s light and clearly see the planet in infrared.
This planet is small, cold, and likely similar in mass to Saturn, making it the lightest directly imaged exoplanet so far.
Previously, finding such small planets with direct imaging was difficult due to their faint heat and the bright glare from their host stars. But Webb’s powerful infrared capability changes that. Scientists say this technique increases the chance of finding Earth-like worlds in the future.
The discovery shows the incredible leap in technology brought by the JWST. It improves direct planet imaging by a factor of 10, and scientists now expect the telescope will help identify even smaller and potentially habitable planets.
The goal is to find rocky planets like Earth or Mars and understand how solar systems form.
In the coming years, even more advanced telescopes will support this search. Instruments like the Extremely Large Telescope in Chile, set to launch in 2028, will help peer deeper into space. Meanwhile, Webb’s discovery of TWA 7b opens a promising chapter in the search for life beyond our Solar System.