Skip to main content Missions Search All NASA MissionsA to Z List of MissionsUpcoming Launches and LandingsSpaceships and RocketsCommunicating with MissionsArtemisJames Webb Space TelescopeHubble Space TelescopeInternational Space StationOSIRIS-RExHumans in Space Why Go to SpaceAstronautsCommercial SpaceDestinationsSpaceships and RocketsLiving in SpaceEarth & Climate Explore Earth ScienceClimate ChangeEarth, Our PlanetEarth Science in ActionEarth MultimediaEarth DataEarth Science ResearchersAbout NASA NASA's ImpactsCenters and FacilitiesDirectoratesOrganizationsPeople of NASACareersInternshipsOur HistoryDoing Business with NASAGet InvolvedContactLearning Resources For Kids and StudentsFor EducatorsFor Colleges and UniversitiesFor ProfessionalsScience for EveryoneSpace Samples for LearningRequest an Exhibit or SpeakerSTEM Engagement at NASAAeronautics Science in the AirNASA AircraftFlight InnovationSupersonic FlightAir Traffic SolutionsGreen Aviation TechDrones & YouTechnology Technology Transfer & SpinoffsSpace Travel TechnologyTechnology Living in SpaceManufacturing and MaterialsRoboticsScience InstrumentsComputingThe Universe ExoplanetsThe Search for Life in the UniverseStarsGalaxiesBlack HolesThe Big BangDark Matter & Dark EnergyThe Solar System The SunMercuryVenusEarthThe MoonMarsJupiterSaturnUranusNeptunePluto & Dwarf PlanetsAsteroids, Comets & MeteorsThe Kuiper BeltThe Oort CloudSkywatchingEspañol CienciaAeronáuticaCiencias TerrestresSistema SolarUniversoScience All NASA ScienceEarth SciencePlanetary ScienceAstrophysics & Space ScienceThe Sun & HeliophysicsBiological & Physical SciencesLunar ScienceCitizen ScienceAstromaterialsAeronautics ResearchHuman Space Travel Research ExploreSearchSubmitNews & EventsMultimediaNASA+
 UniverseCosmic HistoryBuilding BlocksForcesGalaxiesOverviewTypesEvolutionLarge Scale StructuresBlack HolesOverviewTypesAnatomyBlack Hole WeekStarsOverviewTypesMultiple Star SystemsPlanetary SystemsExoplanetsExplorationSensing the UniverseTelescopes 101ObservatoriesMoreNewsDeep DivesQuick ReadsGraphicsGlossaryUniverse HomeExplore This SectionUniverseGalaxiesBlack HolesStarsExoplanetsExplorationMoreUniverse HomeGalaxy BasicsLooking like a pinwheel, this face-on spiral galaxy holds a bright-white core at image center. Arms curve outward from the core. They hold dark dust lanes and bright star-forming regions. All on a black background dotted with stars.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 smallest can contain a few thousand stars and span just a few hundred light-years. Most large galaxies have supermassive black holes at their centers, some with billions of times the Sun’s mass.Galaxies come in a variety of shapes, mostly spirals and ellipticals, as well as those with less orderly appearances, usually dubbed irregular.Most galaxies are between 10 billion and 13.6 billion years old. Some are almost as old as the universe itself, which formed around 13.8 billion years ago. Astronomers think the youngest known galaxy formed approximately 500 million years ago.Galaxies can organize into groups of about 100 or fewer members held together by their mutual gravity. Larger structures, called clusters, may contain thousands of galaxies. Groups and clusters can be arranged in superclusters, which are not gravitationally bound. Superclusters, empty voids, “walls” of galaxies, and other large-scale structures make up the cosmic web of matter in the universe.Our Milky WayOur home galaxy is called the Milky Way. It’s a spiral galaxy with a disk of stars spanning more than 100,000 light-years. Earth is located along one of the galaxy’s spiral arms, about halfway from the center. Our solar system takes about 240 million years to orbit the Milky Way just once.Milky Way illustrationThis illustration shows the Milky Way, our home galaxy.NASA/JPL-CaltechFrom our perspective on Earth, the Milky Way looks like a faint, milky band of light arcing across the entire sky, which is how it got its name. This feature marks the central disk of our home galaxy seen edge on.The Milky Way sits in a neighborhood with over 50 other galaxies called the Local Group. Its members range in size from dwarf galaxies (smaller galaxies with up to a few billion stars) to Andromeda, our nearest large galactic neighbor.The Local Group sits just off the edge of the Virgo cluster and is part of the Laniakea supercluster.Galaxies StoriesExplore All Galaxy StoriesArticle6 min readNASA’s Webb Opens New Window on Supernova ScienceWebb Space telescope deep field image showing hundreds of objects of different colors, shapes, and sizes scattered across the black background of space.Article2 min readHubble Examines a Barred Spiral’s LightA barred spiral galaxy seen face-on. Its many arms and distinct, glowing, bar-shaped core are easily visible. The galaxy’s arms hold bluish patches of older stars, pink patches where new stars are forming, and dark threads of dust. A few bright stars with cross-shaped diffraction spikes lie between us and the galaxy and are visible in the foreground.A close-in view of a barred spiral galaxy. The bright, glowing bar crosses the center of the galaxy, with spiral arms curving away from the bar’s ends and continuing out of view. Bright patches of light where stars are forming surround the bar, which also holds dark lines of dust. The galaxy’s clouds of gas spread out from its arms and bar, giving way to a dark background with some foreground stars and small, distant galaxies.2 min readHubble Views the Lights of a Galactic BarArticle2 weeks ago1 min readWebb Spots a StarburstImage ArticleA close-up view of a spiral galaxy fills most of the scene. It has a bright, glowing spot at its core, broad spiral arms that hold many dark threads of dust, and pink glowing spots across the disk that mark areas of star formation. A faint halo that bleeds into the dark background surrounds the galaxy’s disk.2 min readHubble Captures a Bright Spiral in the Queen’s HairArticle3 weeks agoKeep ExploringDiscover More Topics From NASAUniverseSplotches of bright-pink and blue-white fill the lower half of the image. A bright bar of white stars extends downward from top-center toward the left. Random areas of dusty clouds form dark streams against the bright backdrop.Black HolesStarsExoplanets
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