July 1963: “Ever try to shoot a slow-flying duck while standing rigidly on a fast rotating platform, and with a gun that uses bullets which curve 90° while in flight?”

This question from the July 1963 issue of Lab-Oratory is too perfect to not keep intact. While most of us would need to answer a resounding no, that’s the best metaphor I’ve heard for explaining the complexity of designing spacecraft trajectories.


In 1967, NASA built a trajectory design model during the mission development of the Mariner flybys to help planners illustrate the expected path of the spacecraft. This allowed them to predict not just the trajectory of Mariner 6 and Mariner 7, but also the orientation of the planet. This helped them pinpoint the window of opportunity for scientific instruments and television cameras to collect data during the flyby.

Modern trajectory planning relies heavily on computer-generated plots and animations, allowing for the complex decade-long orbital dance of the Cassini spacecraft around Saturn and its moons and the incredible precision of the MAVEN arrival at Mars.

Image credit: NASA/JPL

Contact the author at mika.mckinnon@io9.com or follow her at @MikaMcKinnon.