Japan is developing a quantum magnetic sensor small enough to be mounted on drones and deployed from warships. The system is designed to detect the faint magnetic signature of submarines from the air — giving Tokyo a new way to track China’s expanding undersea presence.With China’s submarine fleet projected to reach 80 boats by 2035, the technology could have consequences far beyond Japan. Could similar sensors help India monitor underwater activity across the Indian Ocean? Shreya Chandra has moreWatch: https://youtu.be/ZdIztPyHGrs