The Sky at Night — Episode 4: Digging for Dark Matter

You are watching the episode Digging for Dark Matter Scientists are searching for the elusive dark matter 1300 meters below ground. Without it, galaxies would fly apart and the Universe would be very different. Yet there is still no definite proof dark matter exists. Patrick Moore visits Europe's deepest mine, and meets the physicists mining at the frontier of astronomy.Also the latest news from Mars and more on the Kuiper Belt object Sedna.