The first sightings to attract official attention took place on the evening of Dec. 5, 1948, when two pilots flying over New Mexico reported two separate observations, 22 minutes apart, of a pale green light that was visible for no more than a few seconds. The witnesses insisted that it was not a meteor that they had seen, but some kind of strange flare. The next day a minilar "greenish flare" was spotted for three seconds over the supersecret nuclear installations Sandia Base, part of the Kirtland Air Force Base complex in New Mexico.

Also on December 6, the Seventh District Air Force Office of Special Investigations (AFOSD at Kirtland launched a study. And two pilot investigators observed one of the strange objects about 2,000 feet above their aircraft the following evening. They noted that it seemed to move parallel to the earth's surface and that it resembled the flares commonly used by the air force. The lights seemed to have much more intensity, though. It was also larger and more brilliant than a shooting star, meteor, or flare. After a few seconds the objects seemed to burn out and a trail of glowing fragments that were reddish orange in color was observed falling toward the ground.

The next day one of the officers contacted Lincoln La Paz, director of the University of New Mexico's Institute of Meteoritics and an air force consultant on top-secret matters. La Paz acknowledged that the green flares were different from any meteors he had seen himself. From his own observations and those of two other witnesses, from the Atomic Energy Security Service or AESS, La Paz acknowledged that the green flares were different from any meteors he had heard of. Not long afterward, the scientist saw one of the lights himself. From his own observation's commanding officer, he noted that none of the green fireballs had a train of sparks or a dust cloud. This contrasts sharpley with the behavior of meteoritic fireballs.

At La Paz's suggestion, the AESS organized patrols to try to photograph the fireballs. And scientists and engineers at New Mexico's Los Alamos Scientific Laboratory set up a group to study sighting reports. As the number of accounts continued to grow, the army and the air force became more and more concerned: they were especially disturbedwhen LaPaz concluded, by early 1949, that the fireballs were not a natural occurrence, but had been put there by somebody or something.

It was eventually concluded by Los Alamos scientists in 1953 that the objects were not naturally created, but were artificial. Some even believe that they were shot from extraterrestrial spacecraft.