Explore the universe
Navigate everything above Earth through a connected graph of stars, planets, galaxies, missions, and the stories of the sky.
7351 entities · 12867 connections · across science, culture, and astrology
Browse by topic
Each topic is an A–Z index of entities in the knowledge graph.
2998 entities
Stars
Suns near and far — from the brightest in our sky to the Sun's nearest neighbors.
8 entities
Planets
The eight planets of the Solar System.
5 entities
Dwarf Planets
Rounded worlds that share their orbit, from Pluto to Makemake.
24 entities
Moons
Natural satellites orbiting the planets.
145 entities
Galaxies
Island universes of stars, gas, and dark matter.
121 entities
Nebulae
Interstellar clouds where stars are born and where they end.
88 entities
Constellations
The patterns and official regions of the sky.
372 entities
Star Clusters
Groups of stars born from the same cloud.
4 entities
Black Holes
Regions where gravity overwhelms even light.
21 entities
Comets
Icy visitors that grow tails near the Sun.
6 entities
Meteor Showers
When Earth sweeps through cometary debris.
76 entities
Space Missions
Humanity's journeys of exploration beyond Earth.
20 entities
Space Telescopes
Observatories in orbit, above the atmosphere.
25 entities
Observatories
Ground-based facilities that study the sky.
48 entities
Astronomers
The people who changed how we see the cosmos.
80 entities
Space Agencies
The agencies and institutions of spaceflight and astronomy.
55 entities
Launch Vehicles
The rockets that carry missions beyond Earth.
31 entities
Satellites & Stations
Spacecraft and stations in orbit around Earth.
849 entities
Exoplanets
Worlds orbiting other stars, and the systems that host them.
642 entities
Deep Sky
Galaxies, nebulae, clusters, and black holes beyond the Solar System.
25 entities
Catalogs
The great catalogues of the sky — Messier, NGC, and more.
15 entities
Sky Mythology
The myths and figures behind the names in the sky.
115 entities
Night Sky
Events and objects to watch for overhead — showers, comets, and bright constellations.
Explore by connection
Stars in Orion
The bright stars that make up the constellation Orion, the Hunter.
Moons of Jupiter
Jupiter's major moons, including the four Galilean moons discovered by Galileo.
Moons of Saturn
Major moons of Saturn, including Titan and Enceladus.
NASA Missions
Spacecraft and observatories operated by NASA in the knowledge graph.
Missions to Mars
Spacecraft whose mission target is the planet Mars.
Space Telescopes
Orbiting observatories that study the universe from above the atmosphere.
Observed by James Webb
Deep-sky objects the James Webb Space Telescope has studied.
The Solar System
The Sun, planets, and dwarf planets bound by the Sun's gravity.
Greek Mythology of the Sky
Mythological figures linked to the constellations and the night sky.
Deep-Sky Objects
Galaxies, nebulae, star clusters, and black holes beyond the Solar System.
Messier Objects
The deep-sky objects of Charles Messier's catalogue.
NGC Objects
Selected objects from the New General Catalogue.
Moons of Uranus
The major moons of Uranus, named for literary characters.
Launch Vehicles
Rockets that carry missions to orbit and beyond.