The photo above was photographed by the spacecraft New Horizon and was taken in 2007 already but has not been released by NASA until now.

It clearly shows an awesome volcanic eruption on Jupiter’s third moon Io.

Io is the fourth-largest moon in the Solar System and with over 400 active volcanoes, the moon is probably the most geologically active object in the Solar System.

This geologic activity is probably the result of tidal heating from friction generated within Io’s interior when it is pulled between Jupiter and the other moons; Europa, Ganymede, and Callisto.

Several of these volcanoes produce plumes of sulfur and sulfur dioxide that climb as high as 500 kilometers (300 miles) above the surface.

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http://svs.gsfc.nasa.gov/vis/a010000/a011400/a011455/

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