Green Fireballs
Some of the best-documented UFOs were the Green Fireballs seen over the southwestern US, particularly in New Mexico in the 1940s. They were a cause for concern for the US authorities because they were seen mostly above classified military installations, such as the Sandia National Laboratory and Los Alamos. Conspiracy theorists believed that these UFOs were man-made and had military origins, which was why their sightings were mostly around sensitive military bases.
