Astronomy & Space 1-24
24 entries in the Astronomy & Space compendium.
Impact eventCollisions between astronomical objects with measurable effects.Interplanetary mediumThe tenuous plasma and dust filling the Solar System.Interstellar mediumMatter and radiation between star systems in a galaxy.Io (moon)Io is Jupiter's innermost Galilean moon, the most volcanically active body known.Irregular galaxyGalaxies without regular shape, often chaotic and gas-rich.Kuiper beltA circumstellar disc of icy bodies beyond Neptune.Lagrange pointEquilibrium points for small objects in two-body gravitational systems.Lenticular galaxyIntermediate galaxy type with disk and bulge, lacking spiral arms.Light-yearA unit of distance, not time, used for astronomical scales.Local GroupGalaxy group containing the Milky Way and Andromeda.Low Earth orbitLow Earth orbit hosts most artificial satellites and space stations.LuminosityAbsolute measure of radiated electromagnetic energy per unit time.Lunar eclipseA lunar eclipse occurs when the Moon passes through Earth's shadow.Magnitude (astronomy)Logarithmic scale measuring stellar brightness, with lower values for brighter objects.Main sequenceStars spend most of their lives on the main sequence.Mercury (planet)Smallest planet and closest to the Sun.Messier 87A supergiant elliptical galaxy with a relativistic jet and supermassive black hole.Minor planetA Sun-orbiting body that is neither a planet nor a comet.Molecular cloudDense interstellar clouds where stars are born.Nebular hypothesisModel explaining Solar System formation from gas and dust.NovaA stellar explosion on a white dwarf in a binary system.Observable universeThe portion of the universe visible from Earth.Omega CentauriLargest and most massive globular cluster in the Milky Way.Oort cloudTheorized reservoir of icy bodies at the Solar System's edge.
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