epoch of reionisation

When did the lights first come on in the universe? A galaxy close to the dawn of time gives a clue

When did the lights first come on in the universe? A galaxy close to the dawn of time gives a clue

It is springtime in the Northern hemisphere. Countless buds that have been waiting patiently on the stems and branches of trees and shrubs are now blossoming into life. The cosmic equivalent of this season is the time between a few hundred million and a billion years after the Big Bang. This is when the first stars and galaxies ignited, spewing light into the dark universe.