2026-03-26 01:55:30
JWST observes the assembly of a massive #galaxy at z~4: https://arxiv.org/abs/2511.13650 -> "NIRCam images and NIRSpec/IFU spectroscopy (R=2700) show that TGSSJ1530 1049 is part of one of the densest-known structures of continuum and line-emitting objects found at these redshifts. [...] Based on the physical separations and velocity differences between the galaxies, it is expected that these galaxies will merge to form a massive galaxy within a few Gyr. The system qualitatively resembles the forming brightest cluster galaxies in cosmological simulations that form early through a rapid succession of mergers."

