This reprinted book is the first in a new series called MUFON Classics and is considered one of the Top 100 must have books for any serious student of UFOlogy. 
Flying saucers, UFO’s Great Balls of Fire! Where do they come from? What do they want? Why has the air force adopted a policy of silence and ridicule? Do the UFO’s hold the key to man’s future? Do they explain mysteries of the past? Are they only natural phenomena? Or is the planet earth actually being visited by strangers from the skies? This 1966 classic UFO book broke open the discussion with hard to ignore reports from people with nothing to gain including: 
A noted Jesuit Priest-Astronomer 
The American Astronaut who photographed a UFO while orbiting in a manned space flight
 A nine-year-old Brazilian girl who watched a saucer sink into a suddenly boiling river. 
Brad Steiger is the author of 182 books on subjects of UFOs, psychic phenomena and spirituality.