Neil deGrasse Tyson

Dr. Neil deGrasse Tyson (born October 5, 1958) is an astrophysicist and director of the Hayden Planetarium in New York, at the center of the controversy over Pluto's status as a planet.

Character Information
In The Apology Insufficiency, Dr. Tyson stands in a corridor at Caltech, laughing with Raj, where he is introduced to Sheldon. Sheldon quickly points out that Tyson was responsible for the demotion of Pluto as a planet, and liked Pluto, ergo he doesn't like him. Neil deGrasse Tyson defends himself, affirming that he did not demote Pluto but the International Astronomical Union voted as such. Sheldon doesn't concede to Tyson's rebuttal, and Tyson is stupefied by him. He then asks Raj if that is who Koothrappali was telling him about before. Later, Dr. Tyson apologizes to Sheldon in the cafeteria for his role in the Pluto matter, though, an upset Sheldon tells him to shut up.