What it is
Using the Mid-Infrared Instrument coronagraph on JWST, astronomers detected a source 1.5 arcseconds from the young star TWA 7 and interpret it as a cold, sub-Jupiter planet. The planet, TWA 7b, has an estimated mass of about 0.3 Jupiter masses and sits roughly 52 au from its star, a position that accounts for the main gaps and rings in the surrounding debris disc. The host star is only about 6.4 million years old.
Why it matters
This is JWST's first direct-imaging discovery of an exoplanet, and at about 0.3 Jupiter masses it is the lightest planet ever directly imaged, roughly ten times lower in mass than earlier direct detections. It also links a directly seen planet to the ring-and-gap structures long assumed to be carved by unseen planets, closing a gap between indirect signatures and direct proof.
Underlined numbers link to their source. Every metric and quoted figure is listed under Sources and data below.
Filed underexoplanet, JWST, direct imaging, debris disk, planet formation