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New discoveries at Jupiter's moon Ganymede
News story originally written on July 10, 1996

NASA's Galileo spacecraft has transmitted back crisp new images of Jupiter's moon Ganymede which show the moon's surface is daubed by comet and and asteroid impact marks.

In addition to these findings, the researchers have also made a major discovery that Ganymede, which is three-quarters the size of Mars, possesses its own magnetosphere -- a spherical region containing charged particles and magnetic fields. This is the first time that a magnetosphere has been found around a moon. This finding suggests that possible sources of a magnetic field include a molten iron core or even a thin layer of conducting salty water underneath its icy crust.


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