In the film "Galaxy Quest", what was the name of the character played by Sigourney Weaver?

"Galaxy Quest" is a 1999 American science fiction comedy film directed by Dean Parisot and written by David Howard and Robert Gordon. A parody of and homage to science-fiction films and series, especially Star Trek and its fandom, the film stars Tim Allen, Sigourney Weaver, Alan Rickman, Tony Shalhoub, Sam Rockwell and Daryl Mitchell. It depicts the cast of a fictional defunct cult television series, "Galaxy Quest", who are visited by actual aliens who think the series is an accurate documentary, and become involved in a very real intergalactic conflict.

Sigourney Weaver plays the role of Gwen DeMarco, who played Lieutenant Tawny Madison, the ship's communications officer and the only officer aboard who can give orders to the ship's computer.