Geoffrey Alan Landis is an American scientist, working for the National Aeronautics and Space Administration (NASA) on planetary exploration, interstellar propulsion, solar power and photovoltaics. 

Supported by his scientific background Landis also writes hard science fiction. For these writings he has won a Nebula Award, two Hugo Awards, and a Locus Award, as well as two Rhysling Awards for his poetry. He contributes science articles to various academic publications.