A comparison of spot sizes on the asteroid 4 Vesta surface from ground-based and space observations

1Prokofieva-Mikhailovskaia, VV, 1Rublevsk, AN
1Crimean Astrophysical Observatory, Nauchny, Ukraine
Section: Dynamics and Physics of Solar System Bodies
Language: Russian

Crater sizes determined from photographs obtained by the Dawn spacecraft from its orbits around the asteroid 4 Vesta were compared with ones obtained with the use of ground-based spectrophotometric observations and spectral-frequency method (SFM). All the sizes of craters on Vesta were determined with the use of SFM for the processing of equivalent widths of hydrosilicate bands and color indices B – V and V – R. It turns out that the sizes of craters and spots located at the asteroid’s poles correspond to the sizes of spots if it is granted that they are located at 40—45° north and south latitudes. The comparison results for sizes from 10 to 100 km are given in the table. We concluded that SFM allows one to determine sizes of craters on surfaces of asteroids.

Keywords: 4 Vesta, asteroid, crater