SATURN’S MOON HAS ‘ELECTRIC SAND’
If you want to make the best sandcastle in the Solar System, you might want to head to Titan. Researchers at the Georgia Institute of Technology have discovered that grains of sand on the surface of Saturn’s largest moon can become electrically charged, making them stick together more easily.
When wind blows across the moon’s surface at 25km/h or more, the granules swirl into the air and start to collide. As this happens they become charged, like a balloon rubbing against your hair, and stick together. “If you grabbed piles of grains and built a sandcastle on Titan, it would perhaps stay together for weeks due to their electrostatic properties,” said researcher Dr Josef Dufek.
The effect could help to explain the sandy dunes seen on Titan’s surface that can reach heights of 100m, the researchers say.
To make the discovery, the team placed grains of naphthalene and biphenyl – two toxic, carbon- and hydrogen-bearing compounds believed to exist on Titan’s surface – into a rotating nitrogen-filled cylinder for 20 minutes.
“All of the particles charged well, and about
2 to 5 per cent didn’t come out of the tumbler,” explained researcher Méndez Harper. “They clung to the inside and stuck together. When we did the same experiment with sand and volcanic ash using Earth-like conditions, all of it came out. Nothing stuck.”
Earth sand does pick up static electrical charge when it’s moved, but the charges are small and dissipate quickly – this is why you need water to keep the sand together when you are building a sandcastle at the seaside.
Titan, as seen by the Cassini spacecraft