First galaxies
Gas density distribution of the first galaxy after 33 Myr of evolution calculated by Chen & Chen (in preparation). The gas and metals inside supernova remnants mixes with surrounding gas and other remnants and gradually collapses to the galaxy center. There are already over a thousand stars formed in the very central region. The star-forming region is tiny compared with the entire galaxy; thus, the stars are not shown here.
One of the most critical challenges in modern astrophysics is to understand the end of the cosmic dark ages when the first stars and galaxies (i.e., the first luminous structures in the history of the Universe) transformed the dark, simple early Universe into a state of ever-increasing complexity. We (Ken Chen and collaborators) are studying the formation of these first luminous objects with high-resolution cosmological simulations. The figure below shows our ongoing work. We are performing a simulation of first galaxies enriched with metals produced by the first-generation supernovae. This simulation will serve to examine the signature of the metal lines and dust extinction to be detected by a future space telescope, JWST.