Cambridge, Massachusetts - What time is it? The answer, no matter what your initial reference may be a wristwatch, a smartphone, or an alarm clock will always trace back to the atomic clock.

Cambridge, Massachusetts - In classrooms and everyday conversation, explanations of global warming hinge on the greenhouse gas effect. In short, climate depends on the balance between two different kinds of radiation: The Earth absorbs incoming visible light from the sun, called “shortwave radiation,” and emits infrared light, or “longwave radiation,” into space.

Cambridge, Massachusetts - Every day we make simple decisions - what to eat, what to wear - that may be influenced by the views of people around us.

Rochester, Minnesota - DHEA is often touted as an anti-aging therapy, used to ward off chronic illness and maintain energy and vigor. However, most research doesn't back up these claims. Here, K. Sreekumaran Nair, M.D., Ph.D., an endocrinologist at Mayo Clinic in Rochester, Minnesota, answers questions about DHEA.

San Francisco, California - In a nod to the long and rich history of the American steakhouse, OpenTable, the world's leading provider of online restaurant reservations and part of The Priceline Group, is pleased to honor the inaugural 2014 Diners' Choice Award winners for the Top 100 Steakhouses in America. These awards reflect the combined opinions of more than 5 million restaurant reviews submitted by verified OpenTable diners for more than 20,000 restaurants in all 50 states and theDistrict of Columbia.

Huntsville, Alabama - NASA has opened team registration for the 2015 NASA Human Exploration Rover Challenge. Organized by NASA's Marshall Space Flight Center in Huntsville, Alabama, the event will be held April 16-18, 2015, at the U.S. Space & Rocket Center, also in Huntsville.