NASA/Dryden/Carla Thomas

ScienceShot: Halfway Round the World on a Single Tank of Gas

When NASA's fully autonomous plane, Global Hawk, touched down in California's Mojave Desert after a 14-hour, 8300-kilometer round trip to Alaska's Kodiak Island yesterday, it had already matched the endurance of previous scientific missions, manned or otherwise. But it could have kept going. The 15-meter-long craft—previously flown under the U.S. Department of Defense's Defense Advanced Research Projects Agency—landed with enough fuel onboard to take off and fly its air-sampling mission all over again. That's good news for scientists who want to study greenhouse gases, stratospheric ozone, aerosols, and long-range pollutants up into the stratosphere and around the globe, but who don't want to leave the comfort of their home base.