Water combinations on the surface of the asteroid 4 Vesta

The spectral-frequency method (Busarev et al., 2007b) allowed us to obtain data on 16 sizes of hydrosilicate spots on the surface of the asteroid 4 Vesta. Large sizes (800 and 750 km) show clusters of small hydrosilicate spots near a well-known crater. Small spots of 50–13 km cover more than 50% of the surface. The predominant number of small-sized spots suggests their recent origin. Our data confirm the presence of water combinations on the surface of 4 Vesta and allow us to draw a conclusion on their recent appearance in collisions of this asteroid with primitive bodies arriving from the zone of Jupiter.