Dawn spacecraft orbited Vesta for more than one year and collected a hugevolume of multispectral, high-resolution data in the visible wavelengths withthe Framing Camera. We present a detailed disk-integrated and disk-resolvedphotometric analysis using the Framing Camera images with the Minnaert modeland the Hapke model, and report our results about the global photometricproperties of Vesta. The photometric properties of Vesta show weak or nodependence on wavelengths, except for the albedo. At 554 nm, the global averagegeometric albedo of Vesta is 0.38+/-0.04, and the Bond albedo range is0.20+/-0.02. The bolometric Bond albedo is 0.18+/-0.01. The phase function ofVesta is similar to those of S-type asteroids. Vesta's surface shows asingle-peaked albedo distribution with a full-width-half-max ~17% relative tothe global average. This width is much smaller than the full range of albedos(from ~0.55x to >2x global average) in localized bright and dark areas of a fewtens of km in sizes, and is probably a consequence of significant regolithmixing on the global scale. Rheasilvia basin is about 10% brighter than theglobal average. The phase reddening of Vesta measured from Dawn Framing Cameraimages is comparable or slightly stronger than that of Eros as measured by theNear Earth Asteroid Rendezvous mission, but weaker than previous measurementsbased on ground-based observations of Vesta and laboratory measurements of HEDmeteorites. The photometric behaviors of Vesta are best described by the Hapkemodel and the Akimov disk- function, when compared with the Minnaert model,Lommel-Seeliger model, and Lommel- Seeliger-Lambertian model. The traditionalapproach for photometric correction is validated for Vesta for >99% of itssurface where reflectance is within +/-30% of global average.
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