Every second counts when it comes to tsunamis. 🌊 NASA scientists are testing technology that uses GPS to detect tsunamis by the rumble they make in the atmosphere. Called GUARDIAN, the long-term objective is to augment early warning systems. https://go.nasa.gov/45BQzge | NASA Jet Propulsion Laboratory

A tsunami has hit Tonga's largest island, Tongatapu, after an underwater volcano in the South Pacific erupted. | CNN