NASA is bringing back Cold War-era atomic rockets to get to Mars

Nuclear-powered spacecraft would cut travel time to the Red Planet

A mock-up of a full size Nuclear Engine for Rocket Vehicles Application, or NERVA, in 1967. Source: Bettmann Archives via Getty Images

By Stephen Stapczynski

In the race to land humans on Mars, NASA is blowing the cobwebs off a technology it shelved in the 1970s — nuclear-powered rockets.

Last year, NASA partnered with BWXT Nuclear Energy Inc. for an $18.8 million contract to design a reactor and develop fuel for use in a nuclear-thermal propulsion engine for deep-space travel. While that small start is a long way from the the heady days of the Space Race of the Cold War, it marks the U.S. return to an idea that is also being pursued by Russia and China.

A model of a nuclear-powered rocket that uses fission to generate propulsion. Photographer: Science & Society Picture Library via Getty Images

Unlike conventional rockets that burn fuel to create thrust, the atomic system uses the reactor to heat a propellant like liquid hydrogen, which then expands through a nozzle to power the craft.

That doubles the efficiency at which the rocket uses fuel, allowing for a “drastically smaller” craft and shorter transit time, said Stephen Heister, a professor at Purdue University’s School of Aeronautics and Astronautics. “This factor is…