Vesta

Vesta is a large differentiated asteroid in the main asteroid belt, distinguished by its basaltic crust and enormous south-polar impact basins.

Asteroid belt: The region between Mars and Jupiter containing most of the Solar System’s asteroids. Vesta orbits within this population of rocky bodies.
Impact cratering: The formation of a crater when a body collides with a planetary surface at high speed. Impacts carved Vesta’s major basins and scattered its rocks into space.
Eucrite: A basaltic achondrite meteorite rich in calcium and formed from volcanic or shallow intrusive rock. Eucrites represent basaltic material from Vesta’s crust.
Accretion (astrophysics): The growth of a celestial body through the accumulation of smaller particles and objects. Vesta formed as solid material accumulated in the early Solar System.
Heinrich Olbers: A German physician and astronomer who discovered Vesta in 1807. Olbers identified Vesta, then only the fourth known asteroid.
Differentiation (planetary science): The separation of a planetary body's materials into layers of different composition and density. Vesta’s iron core and rocky mantle formed through this process.
Veneneia: A large ancient impact basin in Vesta’s southern hemisphere, partly overlapped by Rheasilvia. Its older structure underlies and predates Vesta’s largest basin.
Diogenite: An achondrite meteorite composed mainly of orthopyroxene and associated with deep crustal rocks. Diogenites expose material from deeper within Vesta’s crust.
Aluminium-26: A short-lived radioactive isotope whose decay supplied heat to early planetesimals. Its decay could melt and differentiate Vesta soon after formation.
Giuseppe Piazzi: An Italian astronomer who discovered Ceres in 1801, the first known asteroid. Piazzi’s discovery began asteroid astronomy six years before Vesta was found.

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