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Multiband Photometry of a Patroclus–Menoetius Mutual Event: Constraints on Surface Heterogeneity

Wong, Ian and Brown, Michael E. (2019) Multiband Photometry of a Patroclus–Menoetius Mutual Event: Constraints on Surface Heterogeneity. Astronomical Journal, 157 (5). Art. No. 203. ISSN 1538-3881. doi:10.3847/1538-3881/ab18f4.

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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 2458217.80943^(+0.00057)_(−0.00050) is 19 minutes 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 ± 0.7 km—slightly larger than the predicted 69.5 km. 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 ~0.15 mag on wide-scale surface color variability across Patroclus.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Wong, Ian0000-0001-9665-8429
Brown, Michael E.0000-0002-8255-0545
Additional Information:© 2019 The American Astronomical Society. Received 2018 October 18; revised 2019 March 1; accepted 2019 April 11; published 2019 May 1. I.W. is supported by a Heising-Simons Foundation 51 Pegasi b postdoctoral fellowship. The Pan-STARRS1 Surveys (PS1) and the PS1 public science archive have been made possible through contributions by the Institute for Astronomy, the University of Hawaii, the Pan-STARRS Project Office, the Max-Planck Society and its participating institutes, the Max Planck Institute for Astronomy, Heidelberg and the Max Planck Institute for Extraterrestrial Physics, Garching, The Johns Hopkins University, Durham University, the University of Edinburgh, the Queen's University Belfast, the Harvard-Smithsonian Center for Astrophysics, the Las Cumbres Observatory Global Telescope Network Incorporated, the National Central University of Taiwan, the Space Telescope Science Institute, the National Aeronautics and Space Administration under grant No. NNX08AR22G issued through the Planetary Science Division of the NASA Science Mission Directorate, the National Science Foundation grant No. AST-1238877, the University of Maryland, Eotvos Lorand University (ELTE), the Los Alamos National Laboratory, and the Gordon and Betty Moore Foundation. This work made use of the JPL Solar System Dynamics high-precision ephemerides through the HORIZONS system.
Group:Astronomy Department
Funding AgencyGrant Number
Heising-Simons Foundation51 Pegasi b Fellowship
University of MarylandUNSPECIFIED
Eotvos Lorand University (ELTE)UNSPECIFIED
Los Alamos National LaboratoryUNSPECIFIED
Gordon and Betty Moore FoundationUNSPECIFIED
Subject Keywords:minor planets, asteroids: individual (Patroclus) – planets and satellites: surfaces – techniques: photometric
Issue or Number:5
Record Number:CaltechAUTHORS:20190501-152046346
Persistent URL:
Official Citation:Ian Wong and Michael E. Brown 2019 AJ 157 203
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:95145
Deposited By: Tony Diaz
Deposited On:01 May 2019 22:32
Last Modified:16 Nov 2021 17:10

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