American graphic designer who worked as a scenic artist on Voyager and Enterprise and wrote the reference book Star Trek Star Charts.
Geoffrey Mandel was active in Star Trek fan publishing in the 1970s and co-created early reference works, including the 1980 Star Trek Maps.
He joined the art department of Star Trek: Voyager as a scenic artist in its later seasons, producing computer displays, signage and alien writing under Michael Okuda's graphic style, and carried on in the same role on Star Trek: Enterprise.
In 2002 he published Star Trek Star Charts, an atlas of the galaxy that later productions have drawn on for their own star maps.