摘要:We present the first complete multiband observations of a binary asteroid mutual event. We obtained high-cadence, high-signal-to-noise photometry of the UT 2018 April 9 inferior shadowing event in the Jupiter Trojan binary system Patroclus–Menoetius in four Sloan bands—g′, r′, i , and z′. We use an eclipse light-curve model to fit for a precise mideclipse time and estimate the minimum separation of the two eclipsing components during the event. Our best-fit mideclipse time of-+2458217.809430.00050 0.00057 is 19minutes later than the prediction of Grundy et al. The minimum separation between the center of Menoetius’s shadow and the center of Patroclus is 72.5±0.7km— slightly larger than the predicted 69.5km. Using the derived light curves, we find no evidence for significant albedo variations or large-scale topographic features on the Earth-facing hemisphere and limb of Patroclus. We also apply the technique of eclipse mapping to place an upper bound of ∼0.15mag on wide-scale surface color variability across Patroclus.
关键词:minor planets, asteroids: individual (Patroclus);planets and satellites: surfaces;techniques:photometric