James Longuski is an American scientist and educator known for his contributions to astrodynamics and space mission design. After working at JPL, since 1988 Longuski has been a professor at Purdue University.
In late 1990s together with Nathan Strange of JPL he developed Tisserand graphs, a method widely used for gravity-assist spacecraft trajectory design. While at JPL Longuski has developed the trajectory for Galileo spacecraft mission.
He has written the popular science book The Seven Secrets of How to Think Like a Rocket Scientist.