Gravitational waves are ripples in time-space that only occur under a handful of extreme cosmic conditions.
Head outside one night this summer and look up. It's amazing what you can see.
International News Editor Richard Stone describes how science in Iran has managed under international isolation, and how it may expand under a new pact.
After 25 years, the Hubble Telescope has provided some of the best book illustrations of all time.
Schaal is known for her innovative research in plant sciences, in addition to her contributions to Washington University in St. Louis, the National Academy of Sciences, and PCAST.