From dead galaxies to mysterious red dots, here’s what the James Webb telescope has found

On this day three years ago, we witnessed the nail-biting launch of the James Webb Space Telescope, the largest and most powerful telescope humans have ever sent into space. It’s explored our own Solar System, studied the atmospheres of distant planets in search of signs of life and probed the farthest depths to find the very first stars and galaxies formed in the universe. JWST has shown our models of how stars drive the chemical evolution of galaxies are still incomplete, meaning we still don’t fully understand the conditions that led to our existence. Adapted from Castellano et al., 2024 The Astrophysical Journal; JWST-GLASS and UNCOVER Teams Small things that ended the cosmic dark arges Using massive clusters of galaxies as gigantic magnifying glasses, JWST’s sensitive cameras can also peer deep into the cosmos to find the faintest galaxies. Adapted from Furtak et al., and Matthee et al., The Astrophysical Journal, 2023-2024; JWST-GLASS and UNCOVER Teams The impossibly early galaxies As well as extremely lively early galaxies, JWST has also found extremely dead corpses: galaxies in the early universe that are relics of intense star formation at cosmic dawn.