NEI Nuclear Notes

Sometimes, irony abounds : When it comes to space travel, plutonium-238 is the perfect fuel: long-lasting and, as I'll explain later, relatively safe. Without it, we have no hope of going much further than Mars, after which it simply becomes too dark to rely on solar panels, the most common alternative power source in space. But the world is rapidly running out of plutonium-238. Where’s the irony? Plutonium-238 is a byproduct of producing plutonium-239, which was used in nuclear weaponry. With the end of the cold war, and the dismantling of much of the nuclear arsenal, there’s no call for plutonium-239. It a case of undoubted progress blocking further progress. Happily, that’s not the end of the story. The government is looking into another way of making plutonium-238. Sarah Zhang at Gizmodo explains the process: The production plan, for now, involves hopping between no fewer than three DOE labs all over the country. Idaho National Laboratory: The precurso...

“If anybody has been harboring doubts about the status of U.S. leadership in space, well, there’s a one-ton, automobile-size piece of American ingenuity, and it’s sitting on the surface of Mars right now.” This statement came from John Holdren , President Obama’s science advisor, this morning following the landing of a 2,000-pound nuclear-powered space rover, Curiosity , on the surface of Mars. This marks the first time that NASA has ever safely landed a human-made object of this size and weight on the surface of Mars, a notable feat in American engineering. Early reports from The New York Times describes the rover’s landing on the Red Planet like a scene in a movie script: As the drama of the landing unfolded, each step proceeded without flaw. The capsule entered the atmosphere at the appointed time, with thrusters guiding it toward the crater. The parachute deployed. Then the rover and rocket stage dropped away from the parachute and began a powered descent toward the surfac...

From Digital Journal : Engineers at NASA’s Kennedy Space Center installed a nuclear power source Thursday onto the Mars rover set to launch this month. The rover, named Curiosity, is the latest in unmanned missions to Mars, and is expected to provide new evidence about Mars history, including clues as to whether the Red Planet ever harbored life. Worth a read. This bit gave us an evil tingle: The nuclear source is also less affected by weather and daylight conditions on Mars, factors that have hampered previous missions, as when the twin Mars Exploration Rovers encountered dust storms that covered their solar panels while operating on Mars from 2004 to 2011. --- The New York Time’s Green blog tries some pushback on Curiosity: One alternative is to develop a better way to convert heat into electricity in space. The National Academy report said that the method NASA uses now is only about 6 percent efficient. A Stirling Engine system could produce five times as mu...