This video is a Tribute to the British astronomer and broadcaster Sir Patrick Moore who died today aged 89. His TV programme The Sky At Night was a great inspiration to me and I believe he would have liked the theory explained in the rest of this video. Sir Patrick presented the BBC programme The Sky At Night for over 40 years, making him the longest-running host of the same television show ever. He wrote dozens of books on astronomy and his research was used by the US and the Russians in their space programmes. His detailed maps of the Moon were used in the Apollo Moon landing.