Amalthea's Density Is Less Than That of Water

  title={Amalthea's Density Is Less Than That of Water},
  author={John David Anderson and Torrence V. Johnson and Gerald Schubert and Sami W. Asmar and Robert A. Jacobson and Douglas V. Johnston and Eunice L. Lau and George D. Lewis and William B. Moore and Anthony H. Taylor and Peter C. Thomas and Gudrun Weinwurm},
  pages={1291 - 1293}
Radio Doppler data from the Galileo spacecraft's encounter with Amalthea, one of Jupiter's small inner moons, on 5 November 2002 yield a mass of (2.08 ± 0.15) × 1018 kilograms. Images of Amalthea from two Voyager spacecraft in 1979 and Galileo imaging between November 1996 and June 1997 yield a volume of (2.43 ± 0.22) × 106 cubic kilometers. The satellite thus has a density of 857 ± 99 kilograms per cubic meter. We suggest that Amalthea is porous and composed of water ice, as well as rocky… 

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