Between December 2020 and March 2021,SpaceX(Hawthorne,CA,USA)launched four prototypes of its Starship,a behemoth rocket intended to one day shuttle people to Mars.Yet,after reach-ing an altitude of several miles and executing a controlled belly flop back toward to the ground,each one exploded in spectacular fashion during or shortly after landing[1].On 5 May 2021,the company achieved success with a fifth Starship,dubbed SN15(Fig.1),which nailed the landing without blowing up[2].As SpaceX-a relative newcomer in the rocketry business-marches forward on its mission to land people on Mars with its distinctive fail-fast,fix-fast approach,government-backed space agencies foresee using half-century-old nuclear propulsion and ion drive technology to ferry astronauts to the red planet and beyond.
"We are seeing from SpaceX a very rapid development process for a system that opens up a huge number of possibilities in space,"said Casey Dreier,senior space policy adviser and chief advocate at the Planetary Society,headquartered in Pasadena,CA,USA.