December 18, 2020 A popular theory of galaxy formation suggests that small galaxies merged to form larger ones. But galaxy C1-23152 – 12 billion light-years from Earth – apparently formed itself from gas in the early universe, via exceedingly rapid star formation. C1-23152 rose to a mass of 200 billion suns in just 500 million years. At the height of its star formation, C1-23152 produced roughly 450 stars per year, or more than one per day. The Milky Way, by contrast, produces about two stars per year. Image via INAF/ HST/ NASA/ ESA. An international team of astronomers said on December 1...