Open AccessThe Orbit and Density of the Jupiter Trojan Satellite System Eurybates–Queta
Author(s) -
Michael E. Brown,
Harold F. Levison,
K. S. Noll,
Richard P. Binzel,
M. W. Buie,
W. M. Grundy,
S. Marchi,
C. B. Olkin,
J. R. Spencer,
Thomas S. Statler,
Harold A. Weaver
Publication year - 2021
Publication title -
the planetary science journal
Language(s) - English
Resource type - Journals
ISSN - 2632-3338
DOI - 10.3847/psj/ac07b0
Subject(s) - trojan , jupiter (rocket family) , asteroid , physics , astronomy , orbit (dynamics) , satellite , spacecraft , astrobiology , asteroid belt , population , satellite system , aerospace engineering , demography , sociology , engineering , gnss applications
We report observations of the Jupiter Trojan asteroid (3548) Eurybates and its satellite Queta with the Hubble Space Telescope and use these observations to perform an orbital fit to the system. Queta orbits Eurybates with a semimajor axis of 2350 ± 11 km at a period of 82.46 ± 0.06 days and an eccentricity of 0.125 ± 0.009. From this orbit we derive a mass of Eurybates of 1.51 ± 0.03 × 10 17 kg, corresponding to an estimated density of 1.1 ± 0.3 g cm −3 , broadly consistent with densities measured for other Trojans, C-type asteroids in the outer main asteroid belt, and small icy objects from the Kuiper Belt. Eurybates is the parent body of the only major collisional family among the Jupiter Trojans; its low density suggests that it is a typical member of the Trojan population. Detailed study of this system in 2027 with the Lucy spacecraft flyby should allow significant insight into collisional processes among what appear to be the icy bodies of the Trojan belt.