On the revision of radiometric albedos and diameters of asteroids

A simple, approximate method is presented for the recalculation of asteroid diameters and geometric albedos given new, improved absolute visual magnitudes. This method avoids recourse to detailed models of an object's reflected and thermally emitted flux components. Its basis is the assumption that for small changes in absolute magnitude the quantity (1-A(v))D-2 can be considered invariant, where A(v) and D are the object's Bond albedo and diameter, respectively. The usefulness of the method for revising the diameters and albedos of asteroids, especially those covered by the IRAS Minor Planet Survey (E. F. Tedesco, Ed., 1992, Tech. Rep. PL-TR-92-2049, Phillips Laboratory, Hanscom AFB, MA), is demonstrated by applying it to a number of objects for which recently updated absolute magnitudes are available. (C) 1997 Academic Press.