Question: In what year was the actor who played Dr. Richard Solomon in "3rd Rock from the Sun" born?

Context articles: Joseph Gordon-Levitt
3rd Rock from the Sun
Harry Solomon
Mary Albright
John Lithgow
Dick Solomon
Chris Hogan
Kristen Johnston
Sally Solomon
French Stewart

Joseph Leonard Gordon-Levitt ( ; born February 17, 1981) is an American actor, filmmaker, singer and entrepreneur.
 As a child, he appeared in the films "A River Runs Through It", "Angels in the Outfield" and "10 Things I Hate About You", and as Tommy Solomon in the TV series "3rd Rock from the Sun".
 He took a break from acting to study at Columbia University, but dropped out in 2004 to pursue acting again.
 He has since starred in "(500) Days of Summer", "Inception", "Hesher", "50/50", "Premium Rush", "The Dark Knight Rises", "Brick", "Looper", "The Lookout", "Manic", "Lincoln", "Mysterious Skin" and "".
 He starred as Philippe Petit in the Robert Zemeckis-directed film "The Walk" (2015), and as Edward Snowden in the Oliver Stone film "Snowden" (2016).
 For his leading performances in "(500) Days of Summer" and "50/50", he was nominated for the Golden Globe Award for Best Actor – Motion Picture Musical or Comedy.
3rd Rock from the Sun (sometimes referred to as simply 3rd Rock) is an American sitcom that aired from 1996 to 2001 on NBC.
 The show is about four extraterrestrials who are on an expedition to Earth, which they consider to be a very insignificant planet.
 The extraterrestrials pose as a human family to observe the behavior of human beings.
Harry S. Solomon is a character in "3rd Rock from the Sun", played by French Stewart.
 He is the brother of Dick Solomon and Sally Solomon, and the uncle of Tommy Solomon.
 His middle initial is mentioned in the episode "Dick the Vote."
 French Stewart said in a 1998 interview, "The way the character was originally described to me was he would be an idiot on any planet.
 So he's got to be the biggest idiot in the universe!"
Mary Margaret Albright is a fictional character who was played by Jane Curtin in the American situation comedy "3rd Rock from the Sun".
 She serves as a straight foil and love interest for the eccentric Dick Solomon.
John Arthur Lithgow ( ; born October 19 , 1945) is an American actor, musician, singer, comedian, voice actor, and author.
 He has received two Tony Awards, six Emmy Awards, two Golden Globe Awards, three Screen Actors Guild Awards, an American Comedy Award, four Drama Desk Awards and has also been nominated for two Academy Awards and four Grammy Awards.
 Lithgow has received a star on the Hollywood Walk of Fame and has been inducted into the American Theater Hall of Fame.
Dr. Richard Solomon, usually known as Dick Solomon, is a character played by John Lithgow in the late 1990s NBC sitcom "3rd Rock from the Sun".
 Solomon is the High Commander of a highly trained alien unit, sent to Earth by their leader, The Big Giant Head.
 His crew is made up of Sally Solomon (played by Kristen Johnston), Harry Solomon (played by French Stewart), and Tommy Solomon (played by Joseph Gordon-Levitt).
 In the first episode, "Brains and Eggs", Dick states that he has made a home of a "third rate planet, has a job at a third rate university, and now we are looking at a third floor apartment."
Christopher "Chris" Hogan is an American stand-up comedian, actor, and comedian, most notable for his membership in the recurring cast of comedians on "MADtv" and for the character of Aubrey Pitman, one of Dick Solomon's students, on "3rd Rock from the Sun".
Kristen Johnston (born September 20, 1967) is an American stage, film, and television actress.
 She is most famous for her role as Sally Solomon in the television series "3rd Rock from the Sun".
 She also starred as Wilma Flintstone in "The Flintstones in Viva Rock Vegas" and as Holly Franklin in the sitcom "The Exes".
Sally Solomon (played by Kristen Johnston) is a fictional character from the television sitcom "3rd Rock from the Sun".
Milton French-Stewart (born February 20, 1964), known professionally as French Stewart, is an American actor and comedian, best known for his role as Harry Solomon on the 1990s sitcom "3rd Rock from the Sun" and for his role as Chef Rudy on the sitcom "Mom".