PASADENA, Calif. – Detailed analysis and review have borne out researchers’ initial interpretation of pebble-containing slabs that NASA’s Mars rover Curiosity investigated last year: They are part of an ancient streambed.
The rocks are the first ever found on Mars that contain streambed gravels. The sizes and shapes of the gravels embedded in these conglomerate rocks — from the size of sand particles to the size of golf balls — enabled researchers to calculate the depth and speed of the water that once flowed at this location. (more…)
PASADENA, Calif. — Researchers using NASA’s Mars Reconnaissance Orbiter see seasonal changes on far-northern Martian sand dunes caused by warming of a winter blanket of frozen carbon dioxide.
Earth has no naturally frozen carbon dioxide, though pieces of manufactured carbon-dioxide ice, called “dry ice,” sublime directly from solid to gas on Earth, just as the vast blankets of dry ice do on Mars. A driving factor in the springtime changes where seasonal coverings of dry ice form on Mars is that thawing occurs at the underside of the ice sheet, where it is in contact with dark ground being warmed by early-spring sunshine through translucent ice. The trapped gas builds up pressure and breaks out in various ways.(more…)
