We are cave people and Ummagumma is a big cigar shaped rock. Remember Star Trek First Contact? The passing Vulcan ship was about to leave when Zephraim Cochran launched his experimental warp drive ship, a converted ICBM, and the Vulcans landed to investigate. If you noticed the looks on their faces they found Americans disgusting but tolerable, learn how to act Japanese and they'll warm up a bit. Maybe by the time science figures out a way to warp space-time and generate enough energy to do it with a contained matter/antimatter reaction the gods will return. They may return sooner if we'd stop shooting at them!