Prospects for Comet Kohoutek (1973f)

Abstract

MANY comets have developed in an extremely irregular and unexpected manner. Large changes of intrinsic brightness have occurred quite suddenly, and curious and rapid changes of shape associated with the coma have often been observed, sometimes with disruption and complete disappearance of the comet. The standard empirical law of brightness is L=L_oδ⁻² r⁻ⁿ where δ and r denote distance from the Earth and Sun respectively ; the index n ranges¹ from about −1.8 to +11.4, with an average value of about 3.3. Although the absolute brightness of most comets increases with diminishing solar distance, the negative values of n arise from a small number that have grown fainter as they approached the Sun.