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Jupiter’s Moons: Crash Course Astronomy #17

Before moving on from Jupiter to Saturn, we’re going to linger for a moment on Jupiter’s moons. There are 67 known moons, and 4 huge ones that we want to explore in greater detail. Ganymede is the largest – larger, in fact, than any other moon in the solar system and the planet Mercury! Callisto, orbiting the farthest out, is smaller but quite similar to Ganymede in many ways. Io, meanwhile, is most noteworthy for its tremendous volcanic activity. There’s also water on Ganymede and Europa!

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Table of Contents
Jupiter Has 67 Moons (4 Big Ones) 0:12
Ganymede is the Largest 1:15
Io is Riddled With Volcanoes 3:16
Europa Has an Undersurface Ocean 4:48
Io, Europa, and Ganymede Interact Gravitationally 3:48
Known Unknowns 8:06

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PHOTO/VIDEO SOURCES
Galileo’s notebook [credit: Image(s) courtesy History of Science Collections, University of Oklahoma Libraries; copyright the Board of Regents of the University of Oklahoma.]
Jupiter’s moons [credit: NASA/JPL/DLR]
Ganymede [credit: NASA/JPL/Ted Stryk]
Interior of Ganymede [credit: Wikimedia Commons / NASA]
Ganymede terrain [credit: Wikimedia Commons / NASA]
Artist Conception of Ganymede (Figure 5) [credit: NASA/ESA]
Callisto [credit: NASA/JPL/DLR]
Interior of Callisto [credit: Wikimedia Commons / NASA]
Valhalla crater on Callisto [credit: Wikimedia Commons / NASA / JPL]
Io [credit: NASA/JPL/USGS]
Io volcano image [credit: NASA/JPL]
Io eruption video [credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute]
Io surface [credit: NASA/JPL/University of Arizona]
Jupiter Magnetosphere Schema [credit: Wikimedia Commons / Volcanopele]
Jupiter aurora [credit: NASA, ESA & John T. Clarke (Univ. of Michigan)]
Europa [credit: NASA/JPL-Caltech/SETI Institute]
Europa ocean [credit: NASA/JPL/Kevin Hand
Habitable zone diagram [credit: PETIGURA/UC BERKELEY, HOWARD/UH-MANOA, MARCY/UC BERKELEY]
Amalthea [c redit: NASA/JPL/Cornell University]