astroengine writes "Hesperia Planum: once a Martian plain — a regular, no-surprises, run-of-the-mill plain. But now, thanks to researchers who used high-resolution imagery from the armada of satellites currently orbiting the Red Planet, Hesperia Planum holds a mystery. Sinuous rilles, a common feature in ancient volcanic regions on Mars and the Moon, appear across Hesperia, but they appear to have no origin and no destination. If they were formed by lava flows, wouldn't they originate near volcanoes? This oddity has led Tracy Gregg and her student Carolyn Roberts of the University at Buffalo to postulate an entirely different rille formation process that could make Hesperia Planum a whole lot more interesting than scientists ever thought."