Second-most Distant Galaxy Discovered Using James Webb Space Telescope

An international team of astronomers led by Penn State researchers has discovered the second-most distant galaxy ever observed using the James Webb Space Telescope (JWST). The galaxy, designated UNCOVER-z13, is located in a region of space known as Pandora's Cluster, or Abell 2744, and is estimated to be about 33 billion light years away from Earth. This means that the light we see from UNCOVER-z13 was emitted when the universe was just 330 million years old, making it one of the earliest known galaxies.

The second- and fourth-most distant galaxies ever seen (UNCOVER z-13 and UNCOVER z-12) have been confirmed using the James Webb Space Telescope's Near-Infrared Camera (NIRCam). The galaxies are located in Pandora's Cluster (Abell 2744), show here as near-infrared wavelengths of light that have been translated to visible-light colors. The scale of the main cluster image is labelled in arcseconds, which is a measure of angular distance in the sky. The circles on the black-and-white images, showing the galaxies in the NIRCam-F277W filter band onboard JWST, indicate an aperture size of 0.32 arcsec. Credit: Cluster image: NASA, UNCOVER (Bezanson et al., DIO: 10.48550/arXiv.2212.04026) Insets: NASA, UNCOVER (Wang et al., 2023) Composition: Dani Zemba/Penn State

UNCOVER-z13 is also notable for its large size. At about 2,000 light years across, it is at least six times larger than the other three galaxies previously located at these extreme distances. This discovery suggests that galaxies may have formed and grown much more rapidly in the early universe than previously thought.

The astronomers used JWST's Near-Infrared Spectrograph (NIRSpec) to study UNCOVER-z13 and other galaxies in Pandora's Cluster. NIRSpec is a powerful instrument that can split light into its component wavelengths, providing detailed information about the composition and properties of galaxies.

The astronomers found that UNCOVER-z13 is a young galaxy with few metals in its composition. This suggests that UNCOVER-z13 is one of the first galaxies to form in the universe, when heavy elements had not yet been created in large quantities.

The discovery of UNCOVER-z13 is a major milestone in our understanding of the early universe. It shows that galaxies were forming and growing much earlier than previously thought, and it provides us with new insights into how the first galaxies formed and evolved.

Journal Information: Bingjie Wang et al, UNCOVER: Illuminating the Early Universe—JWST/NIRSpec Confirmation of z > 12 Galaxies, The Astrophysical Journal Letters (2023). DOI: 10.3847/2041-8213/acfe07