Karen Gillan (Doctor Who's Amy Pond) visits the Royal Observatory, Greenwich to learn about the Prime Meridian Line with space scientist Dr Maggie Aderin-Pocock, and the Great Bear with public astronomer Dr Marek Kukula.
Clip from Doctor Who Confidential, Series 5 Episode 11: Extra Time. First broadcast on BBC Three, 7:30pm Saturday 12 June 2010. Used by permission.