Vesta is about 300 miles in diameter with a surface area about the size of Arizona.
Here is Vesta compared in size to other know rocks in the asteroid belt between Mars and Jupiter.
Vesta spins around once every 5 hours, 20 minutes. It's nearly a sphereoid shape with a huge chunk blasted from its south pole. Vesta is sometimes called 4 Vesta because it was the fourth object discovered in the asteroid belt in 1807.
Image credit: NASA/JPL-Caltech/JAXA/ESA