The Mars Curiosity rover team has selected a rock they’re naming Cumberland as the next drilling target for the rover. The new site lies about 9 feet (3 m) west of John Klein, where Curiosity’s bit drilled its “first bite” into Mars rock back in February.
Both John Klein and Cumberland belong to a geologic layer called “Sheepbed” a layer of mudstone that likely formed a couple billion years ago when streams carrying rocks and mud flowed down the wall of Gale Crater and deposited their burden in a broad alluvial fan. After the streams dried up, the material gradually became compacted into rock; a couple billion year’s later a robotic emissary arrived to piece together the story using with a drill, oven and lasers.
What we know so far is this: John Klein is made of fine-grained mudstone containing clay minerals, sulfate minerals and elements to afford a microbe a happy home. Scientists found sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon in the powder – all This ancient wet environment, unlike some others on Mars, was not harshly oxidizing, acidic or extremely salty but close to neutral, comparable to many water environments on Earth.
Although Cumberland and John Klein are very similar – they’re flat (safe for drilling), criss-crossed by lighter-colored mineral veins and bumpy – Cumberland appears to have more of the erosion-resistant granules that cause the surface bumps.
“The bumps are concretions, or clumps of minerals, which formed when water soaked the rock long ago,” according to a NASA press release.
Sometime in the next few days mission control will direct the rover to the new drilling site and retrieve and analyze a sample of the powdered rock. Not long after, Curiosity will set its sights on the main mission target – the clay-laced slopes of Mt. Sharp, a 3-mile-tall (5 km) mountain inside the crater.
Although the rover’s prime mission lasts 2 years, its plutonium-powered generators have a minimum lifetime of 14 years. Provided Curiosity doesn’t hit a snag, we’ll be raking in the data and rock powder for years to come.