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K magnitudes are given for seven Uranus-occulted stars, together with V and I magnitudes for 20 stars that will be occulted by the Uranian rings in 1986-1990 and 15 that will be occulted by the rings of Saturn in the course of 1986-1991. Occultation stars are noted to be up to 1 mag brighter in the K bandpass than could be predicted on the basis of V-I colors alone; this is explainable in terms of typical degrees of interstellar reddening.

Occultation profiles for the nine confirmed Uranian rings obtained from Las Campanas, the European Southern Observatory, and Cerro Tololo on 15-16 August 1980 are compared. The alpha ring shows a 'double-dip' structure; the eta ring shows a broad and narrow component (similar to Saturn's F ring); and the epsilon ring shows six features that appear in the data from all three observatories. Diffraction fringes appear at the edges of several of the occultation profiles.

Uranus upper atmosphere occultation observations are reported for August 15-16, 1980, and April 26, 1981. Mean atmospheric light curves of 154 + or - 15 K and 132 + or - 15 K, respectively, are derived from the light curves. A comparison of all available Uranus occultation data since March 1977 suggests a significant mean atmospheric temperature change, with a typical 15 K/year variation. It is suggested that molecular and eddy diffusion, together with atmospheric dynamics, are potentially as important as radiation in the upper atmosphere heat balance of Uranus. The close agreement of occultation immersion and emersion temperatures further suggests that effective meridional transport occurs on Uranus.