The diameter, shape, albedo, and rotation of 47 Aglaja

Abstract Observations of the 16 September 1984 occultation of SAO 146599 by 47 Aglaja are reported. Analysis of these observations from 13 sites in the continental United States yields a value of 136.4 ± 1.2 km for the diameter of Aglaja. Based on previously published photometry of Aglaja and new observations given in this paper, the rotational period is 13.20 ± 0.01 hr and the zero-phase-angle visual geometric albedo of the face of the asteroid seen at the time of the occultation is 0.071 ± 0.002. While Aglaja is certainly not perfectly spherical, we argue that a significant portion of the variation with ecliptic longitude of this object's mean brightness must be due to differences in albedo over its surface.