Henrietta Swan Leavitt they became an important part of the evidence that "spiral nebulae" are independent galaxies located far outside of our own Milky Way. Thus, Leavitt's discovery would forever change our picture of the universe, as it prompted Harlow Shapley to move our Sun from the center of the galaxy in the "Great Debate" and Edwin Hubble to move our galaxy from the center of the universe. Leavitt's discovery of a way to accurately measure distances on an inter-galactic scale, paved the way for modern astronomy's understanding of the structure and scale of the universe. The accomplishments of Edwin Hubble, the American
Multiwavelength Atlas of Galaxies Three S classified galaxies are in the Atlas. Active galaxies have Active Galactic Nuclei (AGN) and include LINER, Seyfert, Radio Galaxy, Quasar and Blazar types. 'Activity' refers to non-stellar processes occurring or originating in a galaxy nucleus. An active nucleus has a spectrum with a continuum that cannot be explained by radiation from one or more stellar (or blackbody) objects. Eleven A classified galaxies are in the Atlas. Active galaxies typically have strong emission over a large portion of the electromagnetic spectrum making them prime targets for multiwavelength observations. Hence galaxies categorised Active make up a large fraction (31%) of