研究生科技英语阅读课文翻译对照(46)

之后不明的空中现象频发，在 1948 年美国空军开始对这些报告进行调查，称为 Sign 计划。这一计划的最初动机是怀疑这些 UFO 很可能是苏联尖端飞行器，虽然有些研究员认为它们可能是来自其他世界的飞船，也就是所谓的外星人假说（ETH）。在一年内，Grudge 计划继承了 Sign 计划，到了 1952 年它又被 UFO 官方研究计划中历时最长的 Blue Book 计划取代，其总部位于俄亥俄州代顿市的 Wright-Patterson 空军基地。在 1952 年至 1969 年间，Blue Book 编辑了一万两千多宗目击事件的报告，每一个最后都标上“已确认”或者“未确认”，“已确认”的包括已知的天文现象、大气现象和人造（人为引起的）现象。后者约占总数的 6%，包括了一些信息不足，无法用已知的现象定性的事件。
The Robertson Panel and the Condon Report
Robertson 小组和 Condon 报告
An American obsession with the UFO phenomenon was under way. In the hot summer of 1952 a provocative series of radar and visual sightings occurred near National Airport in Washington, D.C. Although these events were attributed to temperature inversions in the air over the city, not everyone was convinced by this explanation. Meanwhile, the number of UFO reports had climbed to a record high. This led the Central Intelligence Agency to prompt the U.S. government to establish an expert panel of scientists to investigate the phenomena. The panel was headed by H.P. Robertson, a physicist at the California Institute of Technology in Pasadena, Calif., and included other physicists, an astronomer, and a rocket engineer. The Robertson Panel met for three days in 1953 and interviewed military officers and the head of Project Blue Book. They also reviewed films and photographs of UFOs. Their conclusions were that (1) 90 percent of the sightings could be easily attributed to astronomical and meteorologic phenomena (e.g., bright planets and stars, meteors, auroras, ion clouds) or to such earthly objects as aircraft, balloons, birds, and searchlights, (2) there was no obvious security threat, and (3) there was no evidence to support the ETH. Parts of the panel"s report were kept classified until 1979, and this long period of secrecy helped fuel suspicions of a government cover-up.