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 …

Oct 21, 2025 · Galaxy, 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 …

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 …

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.

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...

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 are home to most of the stars in the universe, and they form the beads of the cosmic jewelry that defines structure on the largest scales. But galaxies haven’t always been around, …

Sep 25, 2025 · What Is a Galaxy? 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 called Earth that is …

Oct 21, 2025 · Learn about the three general types of galaxies: spiral, elliptical, and irregular. Almost all current systems of galaxy classification are outgrowths of the initial scheme …

Apr 14, 2025 · Our galaxy, the Milky Way, sits in a Local Group of more than 20 galaxies, but Hubble’s vision takes us far beyond our celestial neighborhood. Galaxies are the visible …