NASA reported on Sept. 15, 2026, that its James Webb Space Telescope had observed IC 348, a star-forming region about 1,000 light-years away in the constellation Perseus, and found brown dwarfs with masses as low as twice Jupiter's mass, or 0.19 percent of the Sun's mass. The agency said these are the least massive brown dwarfs known and that their existence challenges models of star formation.

According to NASA, the team had previously used Webb on IC 348 in 2022, finding brown dwarfs with masses as low as three to four times Jupiter's mass. The researchers used the Near-Infrared Camera in 2024 and followed up with the Near-Infrared Spectrograph in 2025 to study masses through spectroscopy. NASA also reported that one of the lightest brown dwarfs showed signs of a disk, suggesting small planets could be forming around a planet-mass object, and that a spectral feature attributed to an unidentified hydrocarbon appeared in the lowest-mass brown dwarfs studied.

The image also shows protostars in the upper right, including the Herbig-Haro objects HH 797, described as two protostars with nearly parallel outflows, and the propeller-shaped HH 211.