Over subsequent months, Hubble examined other spiral nebulae as he searched for more Cepheids with which to measure distances. Word of Hubble's observations was spreading among astronomers.

Galaxies shine in a rainbow of emissions from gas, dust, and stars. Each of these building blocks emits light at specific ...

Astronomers have captured a stunning, detailed image of the nearby Sculptor galaxy, spanning an impressive 65,000 light years ...

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.

Messier 77, captured by Hubble, also known as the Squid Galaxy, is a swirling spiral 45 million light-years away in Cetus, the constellation named for a whale. It was discovered in 1780 by Pierre ...

SEASON OF THE HARVEST MOON The Spiral Nebulae About Andromeda -- Movements and Occultations of the Planets. Share full article. Sept. 2, 1900. ...

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.

By 1922, he had topped off his survey with a further 17 spiral nebulae, all of which were receding — the fastest at an unprecedented 1,120 miles (1,800 km) per second.

The galactic masterpiece combines over 100 exposures to reveal previously unseen features of stars in formation.

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, ...