NASA's James Webb Telescope discovers a mysterious galaxy emitting ultraviolet radiation.
Produced by Tarun Mishra
Produced by Tarun Mishra
The James Webb Space Telescope (JWST) has detected a galaxy, JADES-GS-z13-1, located just 330 million years after the Big Bang. The brightness of this distant galaxy challenges existing models of the early universe, as it emits ultraviolet radiation that should have been absorbed by surrounding neutral hydrogen.
The discovery was made using the JWST Advanced Deep Extragalactic Survey (JADES), employing the Near-Infrared Camera (NIRCam). The galaxy, observed at a redshift of z=13.05, stands out due to its intense emission of Lyman-α radiation, which is typically associated with active star formation or black hole activity.
According to current cosmological models, the universe during this period was filled with neutral hydrogen, which should have prevented ultraviolet light from traveling freely. The visibility of JADES-GS-z13-1 raises questions about the timing of cosmic reionisation and the transparency of the early universe.
Spectroscopic analysis confirmed the presence of Lyman-α radiation, suggesting either an exceptionally active galaxy or a surrounding region already cleared of neutral hydrogen. This raises the possibility that reionisation may have occurred earlier than expected, driven by unknown astrophysical processes.
Researchers were not anticipating such a bright galaxy at this stage of cosmic evolution. Scientists involved in the study have acknowledged that this finding challenges current theories about the formation of early galaxies and the conditions of the young universe.
One hypothesis suggests that Population III stars—massive, hot stars believed to be the first in the universe—could be responsible for clearing the surrounding hydrogen. Another possibility is that an early supermassive black hole is driving the high luminosity, introducing new considerations for early galaxy formation.
Further observations are planned to determine the precise nature of JADES-GS-z13-1. This discovery may require refinements to the Lambda Cold Dark Matter (ΛCDM) model or even consideration of alternative theories regarding cosmic evolution, reionisation, and the birth of the first galaxies.