This infrared image shows ash spewing out of Iceland's Eyjafjallajokull volcano. It was taken April 17 by a NASA spacecraft. Hotter areas, shown in red, can be seen at the ash plume's base.
NASA/JPL/EO-1 Mission/GSFC/Ashley Davies
The MODIS instrument on NASA's Terra satellite captured an ash plume from the Eyjafjallajokull volcano on Friday. Though satellite images can tell scientists where the ash is, they don't help forecasters determine how much ash is in the air — or at what point it becomes a hazard to airplanes.
MODIS Rapid Response Team/NASA via Getty Images
Smoke and steam hang over the Eyjafjallajokull volcano in Iceland that erupted for the second time in less than a month. The eruption melted ice, shot smoke and steam into the air and forced hundreds of people to flee rising floodwaters.
Gas centrifuges used to produce enriched uranium sit in a plant in Piketon, Ohio, in 1984. The technology for laser-based enrichment is much smaller than technology using centrifuges, and would be easier to secretly develop for weapon production.
At Oak Ridge National Laboratory, an employee works with a mechanical arm to manipulate items inside the radioactive hot cell. The hot cells are used to manufacture new reactor fuel made from spent nuclear waste.
Courtesy of Oak Ridge National Laboratory