The Z machine is located in Albuquerque, N.M., and is part of the Pulsed Power Program, which started at Sandia National Randy Montoya/Sandia National Laboratory hide caption

itoggle caption Randy Montoya/Sandia National Laboratory

Current water-filtering technology is costly, but MIT scientists are testing a simpler and cheaper method that uses wood from white pine trees. Wikimedia Commons hide caption

itoggle caption Wikimedia Commons

About 50,000 years ago, a meteorite struck earth east of present-day Flagstaff, leaving this crater as its calling card. Shane.torgerson/Wikimedia Commons hide caption

itoggle caption Shane.torgerson/Wikimedia Commons

Neonatal nurse Florence Mwenifumbo monitors a newborn receiving bubble CPAP treatment in Blantyre, Malawi. The device was developed by students at Rice University in Houston. Rice 360/Rice University hide caption

itoggle caption Rice 360/Rice University

Dee Faught tests a robotic arm installed on his wheelchair in September. Commercially produced robotic arms can cost tens of thousands of dollars, but three Rice engineering students built one for Dee for about $800. Eric Kayne for NPR hide caption

itoggle caption Eric Kayne for NPR

Dr. Jim Olson meets with Carver Faull at Seattle Children's Hospital in August. Carver, now 12, had surgery to remove a brain tumor in 2012. Matthew Ryan Williams for NPR hide caption

itoggle caption Matthew Ryan Williams for NPR

The image on the left is a piece of lung tissue that contains a tumor viewed under normal white light. The right image shows the same piece of tissue after Tumor Paint has been applied. Here it's viewed under infrared light. Areas that are more red and yellow show a concentration of the paint, which means they are more likely to be cancerous. Courtesy of Julie Novak/Blaze Bioscience hide caption

itoggle caption Courtesy of Julie Novak/Blaze Bioscience

NASA's Solar Dynamics Observatory captured this picture of the sun on June 18. The dark blue area in the upper left quadrant of the sun is a huge coronal hole more than 400,000 miles across. Coronal holes are areas of the sun's outermost atmospheric layer — the corona — where the magnetic field opens up and solar material quickly flows out. NASA/SDO hide caption

itoggle caption NASA/SDO