Speaking of star formation or lack thereof, the oldest ever supernova has been detected by astronomers. This one is some 12 billion years old, one billion years older than the oldest previously known and just 1.75 billion years from the Big Bang.The fact that supernovas are much more luminous that other stars makes it easier to spot them this far out.
But because it's so far away, light reaching us from it has been significantly altered, it's frequency lowered as its wavelength grew due to the expansion of the universe, what is known as redshift.
In a study published in Nature, astronomers talk about two very distant superluminous supernovae, one with a redshift of 2.05, indicating that it is 10.4 billion years away, the other with a redshift of 3.9, 12 billion light years away.
Superluminous supernovae are much brighter than regular supernovae, 10 to 100 times brighter. Obviously, supernovae are already much brighter than regular stars.