Yeah, Anakin Skywalker wouldn’t be a fan. We’re not talking sand like Earth either. Think more along the lines of packing peanuts. Researchers at Georgia Tech conducted a series of experiments to see how sand on Titan acts.
Using a modified pressure vessel, the team tossed in grains of naphthalene and biphenyl (carbon and hydrogen bearing compounds thought to exist on Titan’s surface). Then, they rotated the tube for 20 minutes in a dry, pure nitrogen environment that closely resembles the 98% nitrogen atmosphere of Titan.
The results suggest sand on Titan becomes frictionally charged as they collide in high winds. Once they clump together, they can stay that way for months at a time.
“All of the particles charged well, and about 2 to 5 percent didn’t come out of the tumbler,” said Méndez Harper, the paper’s lead author. “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.”
Sand on Earth picks up electrical charges too, but they are much weaker and dissipate faster. That’s why you can’t just toss sand together to build a sand castle. You need water. But on Titan? The sandcastle building competitions would be epic.
“If you grabbed piles of grains and built a sand castle on Titan, it would perhaps stay together for weeks due to their electrostatic properties,” says Georgia Tech professor Josef Dufek who co-led the study.
This also presents a headache for exploring the moon. Any spacecraft that lands in a sandy region will have a hell of a time keeping it off. “Think of putting a cat in a box of packing peanuts,” Dufek added.
Harper also touches on how the findings could explain one of Titan’s mysteries. Sand dunes on Titan, some towering nearly 300 feet tall, form in the opposite direction of prevailing winds.
“These electrostatic forces increase frictional thresholds,” says Harper. “This makes the grains so sticky and cohesive that only heavy winds can move them. The prevailing winds aren’t strong enough to shape the dunes.”
Credit: G.D. McDonald, J.S. Méndez Harper, NASA, JPL-Caltech, SSI
A 15 mph wind gust on Earth would feel closer to 60 mph on Titan’s surface thanks to its denser atmosphere. And you’ll feel like you’re standing 15 feet underwater because of its higher surface pressure.
Prevailing winds on Titan blow east to west. While the dunes are shaped by winds blowing west to east.
In a 2014 study, researchers from the SETI Institute found the winds on Titan occasionally flip direction and ramp up as the Sun changes position in the sky.
“This work highlights the fact that the winds that blow 95% of the time might have no effect on what we see,” said Devon Burr at the time. The shift in winds doesn’t happen often, but its effects are long-lasting.
Titan is one of the most intriguing worlds in our solar system. But don’t expect to enjoy its beaches. Sure, they might be great for building sandcastles – but oceans full of methane and ethane won’t make for a good swim.