Sublime Fractures

Looking for weird and wonderful landforms that are truly out of this world? Mars has you covered. The planet's south pole is littered with spidery cracks and other peculiar patterns produced by seasonal deposits of frozen carbon dioxide, or dry ice. As spring thaws the south pole each Martian year, the ground warms up faster than the ice, heating it from below. The ice turns directly into a gas through a process called sublimation and starts to accumulate. Rising pressure forces the gas to the surface by carving channels into the ice and underlying terrain. The channels linger long after the ice has melted, growing bigger over time. Explore the images for views of these formations taken by the HiRISE camera aboard NASA’s Mars Reconnaissance Orbiter spacecraft.