Neurologist Francis Jensen examining a teenage patient. Jensen decided to study the teenage brain when her own sons became teenagers. Now Jensen lectures to teens and parents about how teenagers' brains are different. Richard Knox/NPR hide caption

itoggle caption Richard Knox/NPR

Lifelong learning and brain stimulation can help increase memory and decision-making ability, according to neuroscientists. iStockphoto hide caption

itoggle caption iStockphoto

The northern lights dance over the Knik River near Palmer, Alaska. Activity on the surface of the sun creates this natural light show, but severe solar storms could devastate Earth's power and water utilities, and knock out communications. Bob Martinson/AP hide caption

itoggle caption Bob Martinson/AP

A 60-mile-long iceberg known as B9B, right, crashes into the Mertz Glacier Tongue, left, in the Australian Antarctic Territory on Saturday. The collision created a new 48-mile-long iceberg. AP Photo/Commonwealth of Australia hide caption

itoggle caption AP Photo/Commonwealth of Australia