Various asteroid thermal models have been used for the determination of diameters and albedos. The basis of all A simple, approximate method is presented for the recalculation of asteroid diameters and geometric albedos given new, models is the assumption of equilibrium between solar improved absolute visual magnitudes. This method avoids reenergy absorbed and energy emitted as thermal radiation. course to detailed models of an object's reflected and thermally The most commonly used is the so-called Standard Theremitted flux components. Its basis is the assumption that for mal Model (STM) in which the object is assumed to be small changes in absolute magnitude the quantity (1 ุ A V )D 2 perfectly spherical and to rotate very slowly, or have low can be considered invariant, where A V and D are the object's thermal inertia, so that negligible energy is radiated from Bond albedo and diameter, respectively. The usefulness of the the night side. A similar model, the Fast Rotating Model, method for revising the diameters and albedos of asteroids, can be applied to spherical objects that rotate rapidly or especially those covered by the IRAS Minor Planet Survey have high thermal inertia. More accurate and complex (E. F. Tedesco, Ed., 1992, Tech. Rep. PL-TR-92-2049, Phillips thermophysical models can be used but these require Laboratory, Hanscom AFB, MA), is demonstrated by applying knowledge of parameters such as spin axis orientation, it to a number of objects for which recently updated absolute magnitudes are available.