Stars used to be a lot brighter, bigger and denser, study finds
Once the stars died, the conditions needed for their development were never available for them to appear again.
Artist's impression of neutron stars merging, producing gravitational waves and resulting in a kilonova(photo credit: UNIVERSITY OF WARWICK/MARK GARLICK/CC BY 4.0 (https://creativecommons.org/licenses/by/4.0)/WIKIMEDIA)Updated: