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), meaning 'milky', a reference to …

Mar 9, 2026 · 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-years across. The …

Mar 10, 2026 · What is a galaxy? 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 …

Mar 19, 2025 · A galaxy is one of the largest structures in the universe. It is a gravitationally bound system made up of stars, planets, gas, dust, dark matter, and often mysterious phenomena such as …

8 minutes ago · 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.

Nov 8, 2023 · A galaxy is a large system of stars, gas (mostly hydrogen), dust and dark matter that orbits a common center and is bound together by gravity — you can think of them as "island universes."

Jan 18, 2024 · 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.

In these news stories, you’ll find out what we’re learning about how galaxies form, evolve, and shape the beloved universe we call home. While small galaxies are expected to have even smaller satellite …

Galaxies are titanic swarms of tens of millions to trillions of stars, orbiting around their common center of gravity. They also contain interstellar gas and dust. Galaxies show a range of shapes that …

Mar 3, 2026 · A galaxy made almost entirely of dark matter, an elusive form of matter that doesn’t interact with light, was spotted by Hubble 250 million light-years from Earth.