V-type asteroid
A V-type asteroid has a spectrum like the basaltic crust of Vesta and is linked to the HED meteorites.
V-type asteroids have spectra with strong absorption bands from pyroxene, matching the basaltic rocks of 4 Vesta. The V stands for Vesta. Most are small, a few kilometres across or less, and many belong to the Vesta family, a swarm of fragments thought to have been chipped off Vesta by large impacts such as the one that made the Rheasilvia basin.
Their spectra match the HED meteorites, the howardites, eucrites and diogenites. Fragments of V-type asteroids drift slowly, nudged by the Yarkovsky effect, into nearby resonances with Jupiter, from which they can be thrown onto paths that cross Earth's orbit. This is how pieces of Vesta reach us.
A few V-type asteroids lie far from Vesta, in the outer belt, where they cannot easily have come from it. Along with some unusual eucrites with different oxygen isotopes, they suggest there were once other basaltic asteroids, most of which have since been destroyed.
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