422 ] Recognizing the Stars 



in 1947 of disks hurtling through space aroused more amusement 

 than serious attention. It was recalled that fifty years earlier, 

 glimpses of unaccountable "objects" in the skies were exciting 

 people, first in California and later as far east as Chicago. The 

 verdict on the flying saucers was that they were not material 

 objects, but lights and reflections. 



"As Real as Rainbows": Then came a new series of flying saucer 

 episodes. The first reports spoke of round objects hence the name 

 "saucer" but later saucers were described as cone-shaped and 

 even rocket-like in form. Several observers, including an authority 

 on meteors, reported globes of green fire rushing through the night 

 sky which did not seem to be ordinary fireballs. 



These accounts and others like them started some astronomers 

 and the United States Air Force on exhaustive investigations. Dr. 

 Donald Menzel, an astronomer and expert on radar, summed up 

 his researches with the statement: "Flying saucers are as real as 

 rainbows." 



What Causes Optical Illusions: Behind this apparently simple 

 remark are many complicated facts concerned with warm and cool 

 air currents, and lights from cars, airplanes, and other sources, 

 that make us see things when there are none. Even children may 

 be familiar with some simple optical illusions. A common one is 

 to "see" water shining on a road that is actually dry. The effect is 

 caused by a thin layer of warm air above sun-heated pavements. 

 The layer of hot air and another, colder and more dense, above 

 it, together refract (bend) upward the light that comes to them 

 from the sky; and it is this that gives the illusion of a wet 

 pavement. 



Other, less common, types of mirages may explain the majority 

 of flying saucers. In the Southwest, where most of them are re- 

 ported, atmospheric conditions are especially favorable for mir- 

 ages, or "optical ghosts." In some instances, weather balloons or 

 other objects have been mistaken for flying saucers. 



Seeing is not always believing. Our eyes and nature itself often 

 conspire to deceive us. Someday genuine flying saucers, intelli- 



