National Aeronautics and Space Administration (NASA) James Webb Space Telescope (JWST) captures galaxy cluster MACS J1149.5+2223

Key facts

• The National Aeronautics and Space Administration (NASA) James Webb Space Telescope (JWST) has captured a detailed image of the massive galaxy cluster MACS J1149.5+2223.
• The galaxy cluster is located approximately 5 billion light-years away from Earth in the constellation Leo.
• The image demonstrates gravitational lensing, a phenomenon where the immense gravity of the cluster distorts light from background galaxies into arcs and elongated streaks.
• MACS J1149.5+2223 contains over 300 verified galaxies and is identified as one of the largest gravitationally bound objects in the universe.
• A lensed spiral galaxy within the cluster, resembling a pink jellyfish, previously hosted the most distant single star ever discovered and a supernova seen four times due to lensing.
• The observations were conducted using the Near-Infrared Camera (NIRCam), Near-Infrared Spectrograph (NIRSpec), and Near-Infrared Imager and Slitless Spectrograph (NIRISS) instruments.
• The study is part of the Canadian NIRISS Unbiased Cluster Survey (CANUCS) programme, which aims to investigate the first generations of galaxies and the era of reionisation.