
Space & PhysicsMay 1, 1971
The Evolution of Quasars
It seems that they were much more plentiful when the universe was young than they are today. Their light takes so long to reach us that we can observe millions of them that have long been extinct

The Evolution of Quasars
It seems that they were much more plentiful when the universe was young than they are today. Their light takes so long to reach us that we can observe millions of them that have long been extinct