In this NASA/ESA Hubble Space Telescope image, Hubble once again lifts the veil on a famous—and frequently photographed—supernova remnant: the Veil Nebula. The remnant of a star roughly 20 ...

The Hubble constant is one of the most important numbers in cosmology because it tells us how fast the universe is expanding, which can be used to determine the age of the universe and its history. It ...

The two keys to Edwin Hubble's breakthrough discovery were forged by others in the 1910s. The first key, the period-luminosity scale discovered by Henrietta Leavitt, allowed astronomers to ...