A galaxy is a system of stars, stellar remnants, interstellar gas, dust, and dark matter bound together by gravity. [1][2] The word is derived from the Greek galaxias (γαλαξίας), literally …

May 2, 2025 · Galaxies consist of stars, planets, and vast clouds of gas and dust, all bound together by gravity. The largest contain trillions of stars and can be more than a million light …

Nov 27, 2025 · A galaxy is any of the systems of stars and interstellar matter that make up the universe. Many such assemblages are so enormous that they contain hundreds of billions of …

Universe Map is your definitive guide to galaxies, stars, and cosmic structures — mapped, analyzed, and optimized for discovery and research.

Jan 18, 2024 · What is a galaxy, and what are the different types found in the Universe? Find out about galaxy formation and the history of their study.

Mar 19, 2025 · Galaxies are the grand islands of the universe, each one a vast metropolis of stars, gas, dust, dark matter, and endless possibility. From tiny dwarfs to sprawling giants, …

Galaxies are sprawling systems of dust, gas, dark matter, and anywhere from a million to a trillion stars that are held together by gravity. Nearly all large galaxies are thought to also...

Jul 25, 2023 · How many galaxies are there in the Universe? Recent estimates tell us that there could be as many as two trillion galaxies in the observable Universe. Two trillion galaxies is an …

Dec 4, 2025 · Scientists have discovered one of our universe's largest spinning structures. It's a 50-million-light-year-long thread in the cosmic web.

Jun 1, 2017 · The universe is all of the galaxies – billions of them! NASA’s telescopes allow us to study galaxies beyond our own in exquisite detail, and to explore the most distant reaches of …