Geology of 243 Ida
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چکیده
greater than the 1 : 5 ratios common on other rocky bodies. Contributing causes include rim degradation by whole-body The surface of 243 Ida is dominated by the effects of impacts. ‘‘ringing,’’ relatively thin ejecta blankets around crater rims, No complex crater morphologies are observed. A complete or an extended strength gradient in near-surface materials due range of crater degradation states is present, which also reveals to low gravitational self-packing. Grooves probably represent optical maturation of the surface (darkening and reddening expressions in surface debris of reactivated fractures in the of materials with increasing exposure age). Regions of bright deeper interior. Isolated positive relief features as large as material associated with the freshest craters might be ballis150 m are probably ejecta blocks related to large impacts. Evitically emplaced deposits or the result of seismic disturbance dence for the presence of debris on the surface includes resolved of loosely-bound surface materials. Diameter/depth ratios for fresh craters on Ida are p1 : 6.5, similar to Gaspra results, but ejecta blocks, mass-wasting scars, contrasts in color and albedo
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