Patrick Moore

Sir Alfred Patrick Caldwell-Moore (better known as Patrick Moore) is a world-renowned amateur astronomer.

He was mentioned (jokingly) by Rose Tyler when the Doctor asked her who she considered to be the ultimate expert in Alien lifeforms. (DW: Aliens of London)

The Doctor has 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 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. (DW: The Eleventh Hour)