August 03, 2014

1:46 PM | Asteroid scientists vent their concerns about ARM
At first glance, planetary scientists who study asteroids might seem to be obvious supporters of NASA’s Asteroid Redirect Mission (ARM) plans. It would, after all, redirect a small near Earth asteroid (NEA) into lunar orbit, where astronauts would visit it and return perhaps many kilograms of samples. In fact, though, many planetary scientists have expressed [...]

August 02, 2014

2:31 PM | Keeping up with the radioxenons
After the first of two nuclear weapon tests by North Korea, in 2006, a monitoring station in Yellowknife, Canada, caught a whiff of xenon-133, a radioactive isotope of xenon, in the atmosphere. It had been released by the blast and had traveled more than 7,500 km. Being a noble gas, it hadn’t reacted to anything on the way. The Yellowknife… Continue reading Keeping up with the radioxenons
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