Police officers walk past the Washington Convention Center in Washington, D.C., on Saturday, where security is tightening ahead of the Nuclear Security Summit.
Jewel Samad/AFP/Getty Images
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.
Sure they're pretty, but flowers — as well as trees and grasses — release huge amounts of pollen, which isn't great news for pollen-allergy sufferers. For asthmatic kids, these allergies may further aggravate symptoms such as wheezing.
Family, friends and fellow ranchers lined up at the high school field house in Douglas, Ariz., to attend the funeral of Robert Krentz, who was found shot to death on his ranch along the Mexico border last month.
A young woman lights a candle among hundreds of others left by mourners outside the Presidential Palace in memory of late Polish President Lech Kaczynski on Monday in Warsaw, Poland.
Sean Gallup/Getty Image