BBC地平线：我们是外星人 We Are the Aliens (2006)认领

　　Clouds of alien life forms are sweeping through outer space and infecting planets with life – it may not be as far-fetched as it sounds. The idea that life on Earth came from another planet has been around as a modern scientific theory since the 1960s when it was proposed by Fred Hoyle and Chandra Wickramasinghe. At the time they were ridiculed for their idea – known as pansper...