The Air Force was not particularly worried about interplanetary visitors, but it was concerned with the possibility that the fireballs were man-made vehicles, a potential danger to the country. One scientist had suggested that the Russians might have constructed a guided missile whose nose cone, the final stage in a multistage rocket, was made of ice and various other chemicals. In re-entering the earth’s atmosphere, such a cone would burn up; the vaporizing ices would account for the green color observed, for the silent disappearance of the object, and for the lack of material traces on the ground. Whatever the true explanation, members of the Air Defense Command could not afford to guess; they had to know.
In mid-February 1949 they assembled at Los Alamos a conference of military and intelligence officers, physicists, and astronomers, to discuss the problem of the green fireballs. After two days of studying the evidence, most of the members agreed that the fireballs were meteors of an unusual type and, as natural phenomena, not a threat to national security. To take care of the extremely remote chance that this conclusion might be wrong, the conference turned over the problem to the scientists at Air Force Cambridge Research Center which, in the late summer, organized Project Twinkle to equip and establish three cinetheodolite stations in New Mexico. Fitted with a diffraction grating to split the spectrum into its component colors (and thus identify the chemical elements present), the cameras were to photograph and record the altitude, size, speed, and spectrum of the luminous objects.
Since the green fireballs, meanwhile, had all but vanished from the skies, enthusiasm for the research project diminished. Only one camera (designed by Dr. Menzel) was ever put into operation and it never found anything to photograph. After two months of futile searching, the Air Force finally abandoned Project Twinkle as a waste of time.
In the years following, green fireballs occasionally appeared. An astronomer observed one over Lafayette, Colorado, at 7:45 P.M. on June 4, 1950. One soared over the New England states and eastern Canada on November 2, 1950, and a year later, on November 2, 1951, a plane crew over Texas sighted another which was dramatically publicized in Life magazine, and described in another publication as a missile that ejected flaming balls. Few other fireballs made the headlines until the one of September 18, 1954, but even that caused only brief excitement and the Air Force expressed no alarm.
Meteors in the Records
The American Meteor Society, whose members specialize in the study of meteors and meteorites, for years have collected reports of such phenomena. From a large enough number of good descriptions of a given meteor, astronomers can analyze the data mathematically and determine the meteor’s radiant—the point in the heavens from which it seems to come. The meteor is then identified by its radiant and given an AMS number. For several years the data were published in Meteoritics, a journal issued jointly by the Meteoritical Society and the Institute of Meteoritics of the University of New Mexico. Dr. Charles P. Olivier, president of the American Meteor Society, was a contributing editor.
The records in Meteoritics for the years 1950 to 1955 list dozens of fireballs, many of them green, that were somehow overlooked by saucer enthusiasts. On August 11, 1950, during the maximum of the Perseid shower, a blue-green fireball (AMS 2336) apparently oval- or cigar-shaped appeared over Washington, Oregon, and Idaho at 7:30 P.M. and was reported by more than 100 witnesses. So brilliant that it showed a noticeable disk, it flew in a horizontal path, silently broke into three pieces, and disappeared[[V-8], p. 379].
September 20, the same year, was a big day for meteors. At 1:35 A.M. a giant fireball (AMS 2326) roared over southeastern Illinois from north to south, leaving a luminous train visible in five states and illuminating the sky and countryside from St. Louis to Louisville and from Memphis to Knoxville. The final detonation, over western Kentucky, was heard over an area 1000 miles square and shook buildings from Paducah to Memphis. Fragments showered farms over a twenty-five-mile area, struck five buildings, and penetrated one roof. About fifty pounds of meteorites dropped in Murray, Calloway County, Kentucky, and are now in the Smithsonian Institution in Washington. That same night about 10:45 P.M., fireballs were reported by plane crews flying over a six-state area—Idaho, Wyoming, Utah, Colorado, Arizona, and New Mexico[[V-9], p. 115]. Similar fireballs that vanished without trace were reported on September 28, 1953 (AMS 2331); October 4, 1953 (AMS 2330); May 15, 1954; and October 27, 1954 (AMS 2337).
The green fireballs still appear now and then, as they always have. None of them has yet changed into a spaceship.