Guest Stars on "The Big Bang Theory" Quiz

Answer: Stephen Hawking

Stephen Hawking is a cosmologist and theoretical physicist. He suffers from motor neurone disease, being virtually paralysed for many years. His scientific work has resulted in numerous awards and honours and he has also written a number of popular science books such as "A Brief History of Time" (1988) and children's books such as "George's Secret Key to the Universe" (2007).

Answer: Summer Glau

American actress Summer Glau is best known for her science fiction roles. She played Cameron in the TV series "Terminator: The Sarah Connor Chronicles" (to which the title of the episode refers), and also River Tam in the TV series "Firefly" and its film sequel "Serenity".

Answer: Steve Wozniak

Along with Steve Jobs, Steve Wozniak founded Apple Computer in 1976. Engineering rather than management was his passion and he ended up ceasing full-time employment with the company in 1987 to pursue other projects. He designed the Apple I computer (which the company was formed to build) and the Apple II computer.

Answer: Stan Lee

"Excelsior!" was Stan Lee's catch phrase and explains the title of the episode. It also happens to be the motto for New York state. Stan Lee's comic book career started at Timely Comics, which eventually became Marvel Comics. Stan Lee was known (collaborating with others) for introducing the world to such comic book heroes as Spider-Man, The Hulk, the X-Men and Thor.

Answer: He held Tyson responsible for Pluto becoming a dwarf planet

As director of the Hayden Planetarium, Tyson attracted a lot of hate mail for classifying Pluto along with other dwarf planets. Pluto was subsequently demoted in 2006 by the International Astronomical Union to dwarf planet status.

Answer: LeVar Burton

Playing the character Geordi La Forge, Burton started off as helmsman in season one of the "Star Trek: The Next Generation" series before becoming chief engineer for the rest of the series and the four feature films. The character was blind and spent most of the time using a device to provide him with a sense of sight.

In the last three films, he used ocular implants instead. Burton first came to attention for the role of the young Kunta Kinte in the 1977 TV series "Roots".

Answer: James Earl Jones

James Earl Jones supplied the voice for Darth Vader in the original "Star Wars" trilogy. Carrie Fisher also appeared in the trilogy. In an acting career extending over 50 years, James Earl Jones has won many awards. His films include "The Great White Hope" (1970) and "The Lion King" (1994).

Answer: It is a contraction of his surname

Mike Massimino was an engineer and became a NASA astronaut in 1996. His stellar career consists of two Space Shuttle missions (in 2002 and 2009) and four appearances on "The Big Bang Theory".

Answer: Katee Sackhoff

Known more for her TV series rather than her films, Katee Sackoff appeared in "Undressed", "The Fearing Mind" and "The Education of Max Bickford", before landing her role in "Battlestar Galactica". She subsequently appeared in "24" and "Longmire".

Answer: George Takei

George Takei is best known for his role in "Star Trek" or what has sometimes been referred to as "Star Trek: The Original Series". He also played the part in the first six of the "Star Trek" feature films. His appearance in the John Wayne-directed film "The Green Berets" (1968) resulted in Takei missing half of that season's "Star Trek" episodes.