U.S.

Associated Press
Scientist Rick Gaitskell, a physics professor at Brown University, talks Tuesday, May 29, 2012, about the Sanford Underground Research Facility in Lead, S.D. The lab's experiments will include the world's most sensitive dark-matter detector. Gaitskell says that he's been hunting for dark matter for 23 years, and that the lab _ housed inside the now-shuttered Homestake Gold Mine nearly 5,000 feet beneath the earth _ could help scientists understand the origins of the universe. (AP Photo/Amber Hunt)

View gallery

500 photos

National news events

View Comments (1)