The above is a photo of Saturn’s bizarre-looking moon ‘Hyperion’ taken by NASA’s Cassini spacecraft. Hyperion is icy, porous, and sponge-like in appearance and it gives off electrons! When Cassini flew by the Saturn’s moon, it got briefly bathed in “a beam of electrons coming from the moon’s electrostatically charged surface.”
“Its surface is continuously bombarded by ultraviolet light from the sun and exposed to a rain of charged particles — electrons and ions — within the invisible bubble generated by Saturn’s magnetic field, called the magnetosphere.” says NASA for the Hyperion. “The researchers think Hyperion’s exposure to this hostile space environment is the source of the particle beam that struck Cassini.”
During the close encounter with Hyperion, the Plasma Spectrometer aboard Cassini detected that for a brief period of time, the spacecraft had been magnetically connected to Hyperion’s surface and the electron beam escaped from the moon towards the spacecraft.
Analysis indicated that there was a strong negative voltage on Hyperion. “It was rather like Cassini receiving a 200-volt electric shock from Hyperion, even though they were over 2,000 kilometers [1,200 miles] apart at the time,” said Nordheim, one of the team members.
Although no damage has been detected to Cassini due to Hyperion’s electronic beam, it could be hazardous to future robotic and human explorations.