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Next: Worked example 12.2: Acceleration Up: Orbital motion Previous: Planetary orbits

Worked example 12.1: Gravity on Callisto

Question: Callisto is the eighth of Jupiter's moons: its mass and radius are $M= 1.08\times 10^{23}  {\rm kg}$ and $R= 2403  {\rm km}$, respectively. What is the gravitational acceleration on the surface of this moon?

Answer: The surface gravitational acceleration on a spherical body of mass $M$ and radius $R$ is simply

\begin{displaymath}
g = \frac{G M}{R^2}.
\end{displaymath}

Hence,

\begin{displaymath}
g = \frac{(6.673\times 10^{-11})\times(1.08\times 10^{23})}{(2.403\times 10^6)^2} = 1.25 {\rm m/s^2}.
\end{displaymath}



Richard Fitzpatrick 2006-02-02