A galaxy is a vast system of stars, gas, dust, stellar remnants, and dark matter held together by gravity. Galaxies contain everything from young, newly formed stars to ancient stellar populations, along with planetary systems, nebulae, and other astronomical objects. Some also contain supermassive black holes at their centers. Galaxies vary enormously in size, mass, shape, and appearance. 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 part of our solar system. But where is our solar system? It’s a small part of the Milky Way Galaxy. A galaxy is a huge collection of gas, dust, and billions of stars and their solar. Universe Map lets you explore planets, stars, galaxies, nebulae, black holes, and cosmic structures through interactive 3D maps and astronomy guides. Galaxy is a community-driven web-based analysis platform for life science research. What defines a galaxy? A galaxy is a massive, gravitationally bound system. It contains stars, stellar remnants, interstellar gas and dust, and a vast reservoir of invisible material called dark matter. Galaxies vary enormously in size. They range from compact dwarf systems with a few million stars to titanic ellipticals with more than 100. 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 stars. Virtually all galaxies appear to have been formed soon after the universe began, and they pervade all space that is viewable by modern telescopes. 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 Shop Samsung Galaxy smartphones, from the latest foldable phones to everyday devices with Galaxy AI and innovative features. Find yours at Samsung US. Discover the latest in electronic & smart appliance technology with Samsung. Find the next big thing from smartphones & tablets to laptops & tvs & more. A galaxy is a physical system of stars, planetary systems, stellar remnants, substellar objects, 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 the Milky Way galaxy that contains the Solar System. Galaxies, averaging an estimated 100 million stars, [3] range in size from.