Minor planet

A Solar System body that orbits the Sun but is neither a planet nor classified as a comet. Minor planets include asteroids and many trans-Neptunian objects.

Small Solar System body: A Solar System object that is neither a planet nor a dwarf planet, including most comets and small bodies orbiting the Sun. This broader category clarifies how minor planets relate to comets and other non-planetary objects.
Keplerian orbit: An idealized orbit governed by a body's gravity and described by Kepler's laws of planetary motion. Orbital elements describe the paths used to identify and track minor planets.
Near-Earth object: An asteroid or comet whose orbit brings it near Earth's orbital region. Near-Earth minor planets are monitored to assess potential impact hazards.
Asteroid belt: The region between Mars and Jupiter containing most of the Solar System's known asteroids. Its asteroids form the most familiar and numerous minor-planet population.
Giuseppe Piazzi: An Italian astronomer who discovered Ceres in 1801. His discovery began the recognition of a population of small bodies orbiting between Mars and Jupiter.
Planet: A celestial body that orbits a star, is massive enough for gravity to make it nearly round, and has cleared its orbital neighborhood. Clearing an orbital neighborhood distinguishes planets from minor planets.
Orbital resonance: A gravitational relationship in which orbiting bodies repeatedly exert influence at regular integer ratios of orbital periods. Resonances with planets shape the stability and distribution of minor-planet populations.
Planetary defense: The detection and mitigation of threats posed by asteroids or comets that could impact Earth. Tracking hazardous minor planets enables impact-risk assessment and possible deflection.
Trojan asteroid: An asteroid that shares a planet's orbit while residing near one of its stable Lagrange points. Trojan populations demonstrate that minor planets can share planetary orbits in stable configurations.
Ceres: The largest object in the asteroid belt, classified as a dwarf planet since 2006. Ceres was first treated as a planet, then as an asteroid, and later classified as a dwarf planet.

Linked from 9 pages