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Io in eclipse from New Horizons (annotated)

Io in eclipse from New Horizons (annotated)
Io in eclipse from New Horizons (annotated) As New Horizons passed by Jupiter, it saw Io move into Jupiter's shadow. With the Sun blocked from Io's surface, New Horizons could see the light emitted by Io's volcanoes. Each image in this 28-frame animation required an 8-second-long exposure to make the faint glow of the hot volcanoes visible. The long exposures also make background stars visible. In this version of the animation, brighter stars are marked with horizontal white lines. There are a number of artifacts in these images. Large streaks across the photo and the generally bright background result from stray light entering LORRI's barrel -- sunlit Jupiter is not far outside LORRI's field of view, and its brilliant clouds are bouncing light into the camera optics. There is also a lot of "snow" from energetic particles striking the detector. NASA / JHUAPL / SwRI / Emily Lakdawalla