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AsteriaStar
Minor-planet group

Main Asteroid Belt

The reservoir of most asteroids, orbiting the Sun between Mars and Jupiter.

Minor-planet groupRegion: ≈ 2.1–3.3 AU

Overview

The main asteroid belt between Mars and Jupiter, home to the great majority of known asteroids — from the dwarf planet Ceres down to countless small bodies.

Members

16 modelled members.

  • The largest object in the asteroid belt and the closest dwarf planet to the Sun — the first minor planet discovered, and the only one visited by the Dawn orbiter in the inner Solar System.

    CategoryDwarf planetTypeCarbonaceous (C)Diameter939 kmDiscovered1801
  • The second-most-massive asteroid and the brightest as seen from Earth, a differentiated basaltic body and the parent of the Vesta family, orbited by NASA's Dawn.

    CategoryMain beltTypeBasaltic (V)Diameter525 kmDiscovered1807
  • The third-most-massive asteroid, on a notably inclined orbit, the second minor planet ever discovered.

    CategoryMain beltTypeCarbonaceous (C)Diameter513 kmDiscovered1802
  • The fourth-largest asteroid and the largest carbonaceous one, nearly spherical, the parent of the Hygiea family.

    CategoryMain beltTypeCarbonaceous (C)Diameter434 kmDiscovered1849
  • One of the largest main-belt asteroids, a dark, primitive carbonaceous body.

    CategoryMain beltTypeCarbonaceous (C)Diameter332 kmDiscovered1910
  • One of the largest carbonaceous main-belt asteroids — not to be confused with Jupiter's moon Europa.

    CategoryMain beltTypeCarbonaceous (C)Diameter315 kmDiscovered1858
  • One of the largest main-belt asteroids, a dark carbonaceous body.

    CategoryMain beltTypeCarbonaceous (C)Diameter289 kmDiscovered1903
  • The largest stony (S-type) asteroid and the parent of the Eunomia family in the intermediate main belt.

    CategoryMain beltTypeSilicaceous (S)Diameter268 kmDiscovered1851
  • One of the largest asteroids, on a highly inclined orbit, the namesake of the Euphrosyne family.

    CategoryMain beltTypeCarbonaceous (C)Diameter256 kmDiscovered1854
  • A large outer-main-belt asteroid and the first asteroid found to have two moons — Romulus and Remus — making it the first known triple asteroid system.

    CategoryMain beltTypeCarbonaceous (C)Diameter253 kmDiscovered1866
  • The third asteroid ever discovered, a large stony main-belt body — one of the historic first four minor planets.

    CategoryMain beltTypeSilicaceous (S)Diameter233 kmDiscovered1804
  • A large metal-rich main-belt asteroid, the destination of NASA's Psyche mission to study a possible exposed planetary core.

    CategoryMain beltTypeMetallic (M)Diameter222 kmDiscovered1852
  • A large carbonaceous outer-main-belt asteroid, parent of the Themis family, on whose surface water ice has been detected.

    CategoryMain beltTypeCarbonaceous (C)Diameter198 kmDiscovered1853
  • The parent of the large Flora family of stony asteroids in the inner main belt.

    CategoryMain beltTypeSilicaceous (S)Diameter136 kmDiscovered1847
  • The parent body of the Eos family, a large K-type asteroid in the outer main belt.

    CategoryMain beltTypeOtherDiameter104 kmDiscovered1882
  • A Koronis-family main-belt asteroid imaged by the Galileo spacecraft in 1993, which revealed its tiny moon Dactyl — the first confirmed asteroid moon.

    CategoryMain beltTypeSilicaceous (S)Diameter≈ 60 × 25 × 19 kmDiscovered1884

Knowledge connections

Sources

The primary and reference sources this topic draws on.

  • NASANational Aeronautics and Space Administration

    Mission data, planetary science, space telescopes, and public-domain imagery.

    Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.

  • NASA JPLJet Propulsion Laboratory / Solar System Dynamics

    Orbital data, ephemerides, and small-body parameters for planets, asteroids, and comets.