NASA’s Cassini spacecraft spied details on the pockmarked surface of Saturn’s moon Prometheus (86 kilometres, or 53 miles across) during a moderately close flyby on 6 December 2015. This is one of Cassini’s highest resolution views of Prometheus, a moon which orbits Saturn just interior to the narrow F ring, which is seen here at top.
Jupiter’s moon Io is the most volcanically active world in the solar system, with hundreds of volcanoes, some erupting lava fountains up to 250 miles high. New NASA research suggests that tides flowing in a subsurface ocean of molten rock, or magma, could explain why Io’s volcanoes appear in the “wrong” place compared to models that predict how the moon’s interior is heated.
Researchers at Kobe University have used computer models to reveal that Saturn’s F Ring and its shepherd satellites are a natural outcome of the final stage of the planet’s satellite system. This new finding is expected to help elucidate the formation of satellite systems both within and outside our solar system.