A drone with a nose for methane

Unpiloted aircraft, or drones, can sniff methane from hundreds of meters away from the source, making them promising sentries for early detection of natural gas leaks, say researchers from NASA; the University of California, Merced; and the Pipeline Research Council International, an organization of energy pipeline companies. The team announced last week that a 1.7-kg drone known as a quadcopter detected parts-per-billion levels of methane thanks to a miniaturized open path laser spectrometer. Such sensitivity is key to identifying—from the sky—small leaks from natural gas pipelines or storage facilities, says team member Lance Christensen, a chemist at NASA’s Jet Propulsion Laboratory. The sensor’s laser excites methane molecules as they trickle into the instrument, creating measurable disturbances in the optical signal. Ultimately, a network of drones could monitor natural gas infrastructure around the clock, but researchers will need to optimize the detection system first, Christensen says. For example, the team is working to install sensors on small fixed-wing drones, which can fly longer and farther than quadcopters. The drones will also need sensors that can differentiate among methane sources, such as livestock and gas lines, Christensen adds.