The subject of this image bears a remarkable resemblance to a porous sea sponge, floating in the inky black surroundings of the deep sea.
Indeed, the cold, hostile and lonely environment of deep water is not too far removed from deep space, the actual setting for this image in which one of Saturn’s outer moons, Hyperion, can be seen in incredible detail. This image was taken by Cassini when the spacecraft performed a flyby of the small moon on 26 September 2005.
During the flyby, Cassini got more than it bargained for as Hyperion unleashed a burst of charged particles towards the spacecraft, effectively delivering a giant 200-volt electric shock. It appears that Hyperion’s surface becomes electrostatically charged as it is bathed in charged particles – both those constantly streaming out into space from the Sun and those trapped within the magnetic field of the moon’s host planet, Saturn.
Image Source - http://www.esa.int/spaceinimages/Images/2015/04/Saturn_s_sponge-like_moon_Hyperion