NASA’s research into the design and use of nuclear thermal propulsion rockets for future trips to the Moon and Mars has become a higher priority due to additional funding from Congress and changes in U.S. space policy made by the Trump administration.
“America has the nuclear technological capabilities right now to push the boundaries of human exploration further on to mars,” said panelist Rex Geveden at a National Space Council meeting headed by Vice-President Mike Pence in August 2019.
“Many space operations and exploration problems require that high-density power be available or on-call. And there is a class of such problems for which nuclear power is not only the preferred but only solution.”
Geveden added that nuclear-powered rockets would contribute to significantly shorter travel time from Earth to Mars and lower exposure to cosmic radiation by astronauts.
Congress appropriated $125 million for NASA to research and design nuclear thermal propulsion in addition to $100 million appropriated last year.
How Nuclear Thermal Propulsion Rockets Work
This 3-minute NASA video explains how nuclear thermal propulsion rockets work and their efficiency advantages over chemically-propelled rockets.
History of NASA’s Nuclear Thermal Propulsion
The idea of using nuclear thermal propulsion rockets has been around at NASA for decades.
In the 1960s, rocket pioneer Wernher von Braun served as NASA’s Marshall Space Flight Center director and blueprinted use of Nuclear Thermal Propulsion to send astronauts to Mars by the early 1980s.
But shifting priorities, political winds, and space budget cutbacks led to the curtailment of NASA’s nuclear propulsion work at the end of 1972.
But recent advances in materials technology may provide a more affordable pathway to the development of a nuclear rocket engine.
For decades, a range of nuclear propulsion system designs has involved reactors fueled by highly enriched uranium.
“Now we’re looking at systems that use low-enriched uranium,” said Michael Houts, the Nuclear Thermal Propulsion principal investigator on the project at NASA’s Marshall Space Flight Center in Huntsville, Alabama.
NASA has also used nuclear-powered radioisotope thermoelectric generators for spacecraft that travel too far from the Sun to be powered by solar energy.
The launch of two of those nuclear-powered spacecraft, Jupiter-bound Galileo and Saturn-bound Cassini, sparked anti-nuclear protests in 1989 and 1997 outside the south gates of Cape Canaveral Air Force Station in Florida.