Patrick Moore
Sir Patrick Moore was a famous Earth astronomer.
In May 1997, Patrick Moore was interviewed by Eve Waugh on television with Professor Bernard Quatermass regarding the Mars 97 mission. (PROSE: The Dying Days)
He was mentioned (jokingly) by Rose Tyler when the Ninth Doctor asked her whom she considered to be the ultimate expert in alien lifeforms. (TV: Aliens of London)
The Doctor apparently met him at some point in the past, referring to him as "a devil" with the ladies. He was one of many experts holding a conference over the Internet when the Atraxi were threatening to boil the Earth. The Eleventh Doctor, after providing proof that he was a genius, showed the assembled experts how to create a computer virus that would alert the Atraxi to the position of Prisoner Zero. (TV: The Eleventh Hour)
Behind the scenes
Patrick Moore appeared in a real-life segment for Children in Need 1985, in which he "always wanted to open the door of the TARDIS", and does so when it appears, revealing a parade of then-past and present Doctor Who cast members sporting a comically oversized cheque: Patrick Troughton, Carole Ann Ford, Maureen O'Brien, Peter Purves, Michael Craze, Adrienne Hill, Jon Pertwee, Caroline John, Nicholas Courtney, Richard Franklin, John Levene, Elisabeth Sladen, Louise Jameson, Ian Marter, Peter Davison, Janet Fielding (carrying a K9 prop), Matthew Waterhouse, Mark Strickson, Nicola Bryant and Colin Baker.