Add Yahoo as a preferred source to see more of our stories on Google. Small drones can be hard to track at night. Kevin Carter/Getty Images The recent spate of unidentified drone sightings in the U.S.

(The Conversation) – The recent spate of unidentified drone sightings in the U.S., including some near sensitive locations such as airports and military installations, has caused significant public ...

Iain Boyd receives funding from the U.S. Department of Defense and NASA. The recent spate of unidentified drone sightings in the U.S., including some near sensitive locations such as airports and ...