English: Maps of 4 Vesta based on Hubble Space Telescope images obtained in November 1994 with a resolution of about 52 km per pixel.
The top panel shows brightness differences through a 439 nm filter, with the dark feature "Olbers" centered around 0° longitude and 10° N latitude.
The bottom panel is in false-color, correpsonding to spectral (and hence, presumably, composition) differences on the surface. Green colours are thought to represent basaltic lava flows, analogous to the Lunar maria.