In 1920, astronomers Harlow Shapley and Heber Curtis held a Great Debate. Shapley argued that the spiral nebulae were small ...

Around 13.7 billion years ago, something collapsed. It fell outward into the nothingness that stretched in every direction, ...

Edwin Hubble was young and ambitious ... Lemaitre made that connection by realizing that the theory of general relativity described an expanding universe. He recognized that space expanding in between ...

Edwin Hubble was young and ambitious ... by realizing that the theory of general relativity described an expanding universe. He recognized that space expanding in between the galaxies could ...

Ancient ‘white dwarf’ stars explode and die in more ways than was thought, and observing these violent cosmic deaths could ...

The universe appears to be expanding at a staggering speed ... It is named in honor of astronomer Edwin Hubble, who discovered in 1929 that galaxies are moving away from us at a speed proportional to ...

Henrietta Swan Leavitt, an astronomer ahead of her time, discovered the relationship between a star’s brightness and its fluctuation period. This breakthrough allowed Edwin Hubble to measure galaxy ...

Hubble makes his mark Edwin Hubble was young and ambitious ... the astronomers’ annual meeting in Washington, D.C. An expanding universe of galaxies But Hubble wasn’t done.