Jupiter’s Moon Callisto Is Very Likely an Ocean World

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By Sarah Stanley, Eos/AGU. 

Excerpt: A closer look at previously disregarded observations reveals stronger evidence that a deep ocean lies beneath Callisto’s icy surface. ...Cochrane et al. have revisited the Galileo data in more detail. Unlike in prior studies, this team incorporated all available magnetic measurements from Galileo’s eight close flybys of Callisto. Their expanded analysis much more strongly suggests that Callisto hosts a subsurface ocean.... 

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