Costa Rica's Arenal volcano spews lava, ash and toxic gases from its crater.
Getting information on volcanic plumes can be perilous work: the unbearable heat; the noxious gas; the jagged terrain.
So NASA found a new way to avoid putting its researchers in danger - military drones.
Last month, NASA researchers sent three drones into a sulphur dioxide plume emitted by Costa Rica's 3200-metre Turrialba volcano. The team, led by David Pieri of NASA's Jet Propulsion Laboratory in La Canada Flintridge, launched 10 flights with the 2.7-kilogram, twin-electric-engine Dragon Eye planes.
The drones recorded video and collected data using several remote-sensing instruments, sulphur dioxide and particle sensors and automatic atmospheric sampling bottles that measure sulphur dioxide concentration.
''Scientists believe computer models derived from this study will contribute to safeguarding the national and international airspace system and will also improve global climate predictions and mitigate environmental hazards - for example, sulphur dioxide volcanic smog, or 'vog' - for people who live near volcanoes,'' NASA said.
The Dragon Eye drone is built by AeroVironment, the Pentagon's top supplier of small drones.
Drone-makers want to sell their products for use as police helicopters, crop-dusters and hobby aircraft. Drones are not allowed to fly in the US without permission from the Federal Aviation Administration.
Los Angeles Times