Illustration of a human Mars mission concept enabled by nuclear thermal propulsion (NTP). An NTP-powered high performance fission reactor system will significantly reduce the travel time and radiation exposure of astronauts going to and from the Red Planet. Credit: NASA

As NASA finally launches the first Space Launch System (SLS) mission, America is failing to invest in critical space propulsion technology needed to send astronauts to Mars.

The United States must develop space nuclear propulsion technologies to enable 21st-century human missions to Mars. Congress should immediately direct NASA and the Department of Energy to partner with a University Affiliated Research Center or Federally Funded Research and Development Center to create a new National Space Nuclear Propulsion Laboratory.

It is naive and against national interests for the U.S. to rely on expensive, outdated, slow, single-use chemically propelled rockets like SLS to transport astronauts to Mars. Instead, America must aggressively invest in developing space nuclear propulsion systems.

Nuclear technology, including nuclear electric propulsion (or “NEP”) and nuclear thermal propulsion (or “NTP”), will be a space travel game-changer with profound implications for deep space mission speed, agility and capability.

The increased propulsive power of nuclear systems will allow humans to head to Mars on a more regular cadence than the current mission launch windows of “every 26 months.” Nuclear propulsion also will allow power for astronauts on Mars missions to abort and return to Earth in the event of an emergency.

A recent National Academies of Sciences study concluded that the U.S. should further study both NEP and NTP systems for human Mars missions but stopped short of prioritizing the two. The experts concluded that if the U.S. starts serious development of an NTP system today, we might have an operational system by 2039, our back-of-the-napkin date for a first American human mission to Mars. An NTP system would provide fast, effective propulsion for our human missions to Mars.

Graphic showing a notional transit habitat mission to Mars using a nuclear electric propulsion (NEP) propulsion system. Nuclear propulsion systems will provide significant advantages over conventional chemical propulsion systems, providing robust power while enabling more flexibility in human Mars mission architectures. Credit: NASA

A NASA colleague once brilliantly explained that NEP and NTP are the difference “between a Prius and a Porsche.” Both cars will get you to a destination, but each at different speeds and with different trade-offs.

Having both systems operational would provide decades of capability and throw the doors of human deep space exploration wide open. This new technology development will be no easy task — both NEP and NTP systems need significant technology research and development now to create working systems ahead of other space-faring nations.

As America did with the Apollo Program, we’ll have to start from scratch, inventing new materials, engines and nuclear systems that just don’t exist today. This is why we need action now.

To enable these new nuclear propulsion systems, we should rely on the real brain power of our nation – our academic institutions and American industry.

While some brilliant small R&D projects have taken place in federal agencies like DARPA (their DRACO mission) and NASA (their Fission Surface Power project), government agencies lack the cutting-edge facilities and intellectual capacity to make this essential tech development R&D come to fruition by the mid-2030s.

Leadership of a new national lab by a university-affiliated partner will produce significant government cost savings. Combining the smarts of academia with the lean business sense of industry will be far more cost effective than earmarking this work to be done in tiny increments by government agencies that are not prepared to take on this technology challenge.

Federal agencies should provide the funding and the real property, along with security and safety oversight and services to the new lab, led by a university-affiliated organization. Academia and industry will always find ways to do the actual R&D faster, better and cheaper than government bureaucrats.

American industry is more than ready to join in this important aerospace technology race. America’s best and brightest from multiple business sectors can knock down the long pole of space nuclear propulsion while advancing practical commercial uses of this new technology capability, right here on Earth. Like any new disruptive technology, economic opportunity and societal benefit will follow once these systems are proven through in-space demonstration missions.

It’s time to stop waiting for obtuse space policy scribblings about extended study and analysis to appear from the Space Council or other administration oracles. Congress should direct the formation of a new hybrid national lab dedicated to creating and demonstrating advanced space nuclear propulsion systems within a decade. Without immediate Congressional direction, America will continue to fall behind in a critical technology needed to power our future human exploration of deep space.


David Steitz most recently served as NASA’s deputy associate administrator for technology, policy and strategy and as the agency’s deputy chief technologiest. Steitz retired from NASA in May, concluding a 32-year career at NASA Headquarters in Washington.

This article originally appeared in the September 2022 issue of SpaceNews magazine.