[{"n": "Impact event", "u": "/e/astronomy-and-space/impact-event/", "s": "Collisions between astronomical objects that shape planets and life."}, {"n": "Interplanetary medium", "u": "/e/astronomy-and-space/interplanetary-medium/", "s": "The interplanetary medium is the mass and energy filling the Solar System, consisting of solar wind plasma, du"}, {"n": "Interstellar medium", "u": "/e/astronomy-and-space/interstellar-medium/", "s": "Matter and radiation between star systems in a galaxy."}, {"n": "Io (moon)", "u": "/e/astronomy-and-space/io-moon/", "s": "Io is Jupiter's innermost Galilean moon, the most volcanically active body known."}, {"n": "Irregular galaxy", "u": "/e/astronomy-and-space/irregular-galaxy/", "s": "Galaxies without a distinct regular shape, often chaotic in appearance."}, {"n": "Kuiper belt", "u": "/e/astronomy-and-space/kuiper-belt/", "s": "A circumstellar disc of icy bodies beyond Neptune."}, {"n": "Lagrange point", "u": "/e/astronomy-and-space/lagrange-point/", "s": "Equilibrium points for small objects in two-body gravitational systems."}, {"n": "Lenticular galaxy", "u": "/e/astronomy-and-space/lenticular-galaxy/", "s": "Intermediate galaxy type with disk and bulge, lacking spiral arms."}, {"n": "Light-year", "u": "/e/astronomy-and-space/light-year/", "s": "A unit of distance, not time, used for astronomical scales."}, {"n": "Local Group", "u": "/e/astronomy-and-space/local-group/", "s": "Galaxy group containing the Milky Way and Andromeda."}, {"n": "Low Earth orbit", "u": "/e/astronomy-and-space/low-earth-orbit/", "s": "Low Earth orbit hosts most artificial satellites and space stations."}, {"n": "Luminosity", "u": "/e/astronomy-and-space/luminosity/", "s": "Absolute measure of radiated electromagnetic energy per unit time."}, {"n": "Lunar eclipse", "u": "/e/astronomy-and-space/lunar-eclipse/", "s": "A lunar eclipse occurs when the Moon passes through Earth's shadow."}, {"n": "Magnitude (astronomy)", "u": "/e/astronomy-and-space/magnitude-astronomy/", "s": "Logarithmic scale measuring stellar brightness, with lower values for brighter objects."}, {"n": "Main sequence", "u": "/e/astronomy-and-space/main-sequence/", "s": "Stars spend most of their lives on the main sequence."}, {"n": "Mercury (planet)", "u": "/e/astronomy-and-space/mercury-planet/", "s": "Smallest planet and closest to the Sun."}, {"n": "Messier 87", "u": "/e/astronomy-and-space/messier-87/", "s": "A supergiant elliptical galaxy with a relativistic jet and supermassive black hole."}, {"n": "Minor planet", "u": "/e/astronomy-and-space/minor-planet/", "s": "A Sun-orbiting body that is neither a planet nor a comet."}, {"n": "Molecular cloud", "u": "/e/astronomy-and-space/molecular-cloud/", "s": "Dense interstellar clouds where stars are born."}, {"n": "Nebular hypothesis", "u": "/e/astronomy-and-space/nebular-hypothesis/", "s": "Model explaining Solar System formation from gas and dust."}, {"n": "Nova", "u": "/e/astronomy-and-space/nova/", "s": "A stellar explosion on a white dwarf in a binary system."}, {"n": "Observable universe", "u": "/e/astronomy-and-space/observable-universe/", "s": "The portion of the universe visible from Earth."}, {"n": "Omega Centauri", "u": "/e/astronomy-and-space/omega-centauri/", "s": "Largest and most massive globular cluster in the Milky Way."}, {"n": "Oort cloud", "u": "/e/astronomy-and-space/oort-cloud/", "s": "Theorized reservoir of icy bodies at the Solar System's edge."}, {"n": "Orbit", "u": "/e/astronomy-and-space/orbit/", "s": "Curved trajectory of an object under an attracting force."}]