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Where Have All Our Visitors Gone Sixty years ago, a man named Kenneth Arnold saw something that people are still (51) today -something that changed popular culture for ever. Flying his plane over mountains in the US state of Washington, he saw a line of strange objects, either crescent -shaped or disc-like, flying (52) the motion of a saucer skimming on water. The media soon picked up on the story -the Flying Saucers were here! Was the earth being (53) by creatures from another planet Soon, so many sightings were made that the US military began to (54) . It called these strange objects UFOs -Unidentified Flying Objects, and that is how they are (55) today. Military investigations found no evidence of visitors from outer space. But that did not stop the true (56) . The military were (57) up, they said. Or (58) it was because the travelers from space were of such superior intelce that they could hide from the most sophisticated military ysts. People have always seen strange lights in the sky. In the past these were explained in (59) ways. In a world where religion was less influential and science fiction was popular, signs from god were replaced by visitors from other (60) . The date of the first UFO signings was also significant. In 1947, World War Ⅱ had just ended and the (61) war was just beginning. Humanity seemed locked in endless conflicts. Like generations before them, people looked (62) the skies for help. But instead of seeking God, they looked for help from super-intelt aliens with (63) technology. Belief in UFOs became the first religion of science. However, even people who believe in UFOs are not quite sure why they visit the earth. The universe is a big place and it is () to assume that there is life somewhere out there. It is possible that aliens have worked out how to travel through space. Yet some people report that they have been taken by aliens and have had experiments (65) on them. Why would anyone travel across half the universe to conduct medical experiments on people living in small towns in the United States