
- Galaxy - Wikipedia- 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 … 
- Galaxy | Definition, Formation, Types, Properties, & Facts | Britannica- Oct 21, 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 … 
- Galaxies - NASA Science- 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 … 
- What Is a Galaxy? - Scientific American- May 9, 2025 · In modern times, though, we use “galaxy” more generically to refer to any large system of stars, gas, dust and dark matter, all held together by their mutual gravity. 
- What’s a galaxy? All you need to know - EarthSky- Mar 23, 2025 · A galaxy can contain hundreds of billions of stars and be many thousands of light-years across. Our own galaxy, the Milky Way, is around 100,000 light-years in diameter. 
- Galaxies—facts and information | National Geographic- 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 contain... 
- What Is a Galaxy? | NASA Space Place – NASA Science for Kids- Sep 25, 2025 · What Is a Galaxy? The Short Answer: A galaxy is a huge collection of gas, dust, and billions of stars and their solar systems, all held together by gravity. We live on a planet … 
- What is a galaxy? - BBC Sky at Night Magazine- A galaxy is a concentration of millions or billions of stars, gas clouds and pockets of dust, all bound by gravity and swathed in a cocoon of mysterious dark matter. 
- What is a Galaxy? - sciencenewstoday.org- Mar 19, 2025 · The Basics: What Is a Galaxy, Really? At its core, a galaxy is a massive, gravitationally bound system consisting of stars, stellar remnants, interstellar gas, dust, and … 
- Galaxy - ESA/Hubble- Galaxies are collections of stars, dust, gas, and dark matter, which are bound together by the gravitational attraction that results from their own mass. A small dwarf galaxy contains a few …