The Andromeda Galaxy, located 2.5 million light years away, has fascinated observers for centuries. Once believed to be part ...

A third category – nebulae with spiral structure – particularly intrigued astronomers. The Andromeda nebula, M31, was a prominent example. It’s visible to the naked eye from a dark site.

Hubble worked hard, taking images of spiral nebulae every clear night and looking for the telltale variations of Cepheid variables. By the end of 1924, he had found 12 Cepheids in M31.

About 100 years after astronomer Edwin Hubble's discovered the "magnificent" spiral nebula, the Hubble Space Telescope and NASA scientists have produced the most comprehensive survey of the ...

The powerful device will scan the sky like never before, capturing vast amounts of data to reveal how the universe changes ...

The headline read: Finds Spiral Nebulae are Stellar Systems: "Dr. Hubbell Confirms View That They Are 'Island Universes'; Similar to Our Own." On Sunday November 23, 1924, ...

M51’s pronounced arms caused astronomer William Parsons, Earl of Rosse, to call it a “spiral nebula” in 1845. In the two centuries that followed, ...

Many scientific terms are very specific, but the term nebula is, well, nebulous. In a very generic sense, it simply means a fuzzy thing. But there are a wide variety of astronomi ...

Putting Isaac Roberts’ astonishing 1888 photographs of the Great Nebula in Andromeda and other spiral nebulae to cosmic effect at his argument’s outset, Pettigrew then immersed the reader in a ...