The constitution of cometary nucleiThe nongravitational term in the expression for the total force acting on a comet is calculated, and an upper limit is obtained for the product of the radial nongravitational term times the radius times the square root of the albedo. This condition is satisfied for ten periodic comets with q no greater than 1.5 AU, and the activity of these comets is consistent with control by H2O ice. Some of the comets must be spotty to account for their low albedo values. The effect of cosmic rays on comets, leading to frosting of their surface, is discussed.
Document ID
19780035845
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Whipple, F. L. (Harvard College Observatory and Smithsonian Astrophysical Observatory, Center for Astrophysics, Cambridge Mass., United States)