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Title: MOSEL Survey: Tracking the Growth of Massive Galaxies at 2 < z < 4 using Kinematics and the IllustrisTNG Simulation
Authors: Anshu Gupta et al.
First Author’s Institution: University of New South Wales, Australia
Status: Published in ApJ
How, exactly, galaxies form is still very much an open question in astrophysics. It’s not like we can watch a galaxy evolve — most are about 12 billion years old, and even the youngest we’ve discovered is about 500,000 million years old.
There are two ways to work around this problem. The first is a simple matter of looking back into time. Light takes a finite amount of time to travel to us, and so the farther away we look, the older that light is. That means that the farther a galaxy is, the younger we see it. Instead of watching a single galaxy evolve over time, we can compare farther (“younger”) galaxies ...