Layers formed when ice accumulated at the poles during past ice ages on Mars. But each time the planet went through a warming cycle, a remnant of the ice caps became covered by sand, which protected the ice from solar radiation and prevented it from dissipating into the atmosphere. If melted, the newly discovered polar ice would be equivalent to a global layer of water around Mars at least 1.5 meters (five feet) deep.
“Each layer of this mountain is a puzzle piece,” said Curiosity Project Scientist Ashwin Vasavada of JPL about the Mars epi-center of NASA’s Curiosity mission’s goal, Gale Crater’s Mount Sharp. “They each hold clues to a different era in Martian history. We’re excited to see what this first sample tells us about the ancient environment, especially about water.”