Why the US can’t send humans to Mars

1960s: Mars by 1965

In the late 1950s, Theodore Taylor, who worked on nuclear weapons at Los Alamos, and the theoretical physicist Freeman Dyson embarked on an ambitious plan to build a nuclear-explosion-powered spaceship.

By 1963, the team was having trouble getting increased funding. That same year, the Limited Test Ban Treaty was signed, hampering the team’s ability to test its vehicle.

The project was canceled a year later.