Mysterious UV Radiation in Young Stars Baffles Astronomers Using James Webb

Astronomers have discovered a puzzling phenomenon that challenges existing ideas about star formation. Using the James Webb Space Telescope, the team at the Max Planck Institute for Radio Astronomy observed intense ultraviolet radiation in five young protostars. Their findings suggest the radiation comes from within the star systems themselves, not from external sources. The research, led by Agata Karska, focused on protostars in the constellation Ophiuchus, about 450 light-years away. These stars were still surrounded by thick gas and dust, with surface temperatures too low to produce strong ultraviolet light naturally. Yet, the telescope’s Mid-Infrared Instrument detected clear signs of such radiation, including heated molecular hydrogen and ionised particles.

Initially, scientists suspected massive nearby stars might be the cause. However, the conditions ruled this out. The radiation levels were consistently high across all five protostars, pointing to a local origin. Karska explained that the most likely source is violent shockwaves from fast-moving gas streams colliding with the star’s disk or jets blasting from its poles, directly affecting the surrounding molecules.

The team published their results in the journal Astronomy & Astrophysics. The discovery, if confirmed, could reshape our understanding of planet formation and the chemistry of protoplanetary disks. It highlights how internal processes in young star systems may play a larger role in their development than previously thought.