1The spacecraft's ion propulsion system allowed it to achieve unprecedented speeds over the course of its decade-long mission.
2Is electromagnetic propulsion a viable alternative to chemical rockets for interplanetary travel, given current technological constraints?
3The submarine's pump-jet propulsion was not designed for raw speed but for near-silent operation in contested waters.
4Consider how the evolution of cephalopod jet propulsion has inspired a new generation of soft-bodied underwater drones.
5There is a fundamental elegance in the biological propulsion of a falcon's stoop, a conversion of gravitational potential into kinetic force that no engine has yet matched.