No Large Brightness Variations on Nereid

Abstract Observations of Nereid with the 200-in. telescope on Palomar Mountain over three contiguous nights in July 1995 show no evidence for the large photometric variations seen by earlier observers. Total brightness variations within a single night are less than 10%. Our results suggest that Nereid may have a long rotational period, perhaps on the order of weeks. Our observations were not obtained close enough to Nereid's apoapsis to determine whether its rotation state is chaotic, as suggested by Dobrovolskis (1995, Icarus 118, 181–198).