Ghost Stars of the First Billion Years

Type Ia supernovae



When small, dense stars called white dwarfs explode, they produce bright, short-lived flares called Type Ia supernovae. These supernovae are informative cosmological markers for astronomers—for example, they were used to prove that the universe is accelerating in its expansion.


Hubble’s Constant -The Expanding Universe Past, Present & Future

Hubbles Constant


Arguably the most important Cosmological discovery ever made, Hubble’s Constant, is that our universe is expanding. Its stands, observes the Harvard -Smithsonian Center for Astrophysics, along with the Copernican Principle — that there is no preferred place in the universe, and Olbers’ paradox — that the sky is dark at night, as one of the cornerstones of modern cosmology.