National Academy of Sciences Reports, Nuclear Propulsion Is Essential for Human Mars Exploration
Feb. 15 , 2021 (EIRNS)—The National Academy of Sciences, Engineering and Medicine has produced a report—commissioned by NASA—which lays out a pathway for the United States to begin human exploration of the Solar System beyond the lunar orbit. Stopping just short of mandating nuclear propulsion, the report, “Space Nuclear Propulsion for Human Mars Exploration,” makes clear that current modes of chemical propulsion are inadequate and that therefore a breakthrough is necessary.
“NASA should commit within the year to conducting an extensive and objective assessment of the merits and challenges of using different types of space nuclear propulsion systems,” reads the press release, “and to making significant technology investments this decade. Such a program must include subsystem development, prototype systems, ground testing, and cargo missions as a means of flight qualification prior to first crewed use.”
While fission energy for space propulsion is less capable than a system that uses fusion power (increased energy density), a fission drive would provide an incremental increase in propulsion efficiency as compared to today’s chemical rockets. NASA has started and stopped a half-dozen space nuclear power projects, needed for manned deep space travel since the 1960s.
While not (yet) addressing the question of fusion propulsion, the report—a 104-page “consensus report” of the NAS’s Aeronautics and Space Engineering Board’s Space Nuclear Propulsion Technologies Committee—“assesses the primary challenges, merits, and risks for developing a nuclear electric propulsion (NEP) system and a nuclear thermal propulsion (NTP) system for a human mission to Mars.”
NASA has the official goal—announced in 2015—of sending a four-person crewed mission to Mars, launching in 2039. Bobby Braun, director for planetary science at the Jet Propulsion Laboratory and co-chair of the committee that wrote the report, said, “Space nuclear propulsion technology shows great potential to facilitate the human exploration of Mars. However, significant acceleration in the pace of technology maturation is required if NASA and its partners are to complete this mission within the stated timeline.”
In their review of the report, Ars Technica illustrated the problem bluntly, saying that, “relying on chemical propulsion to venture beyond the Moon probably won’t cut it. The main reason is that it takes a whole lot of rocket fuel to send supplies and astronauts to Mars.” They calculate that, just to get the fuel for the spacecraft into orbit would take 10 launches of the SLS rocket at a cost of $2 billion each, or $20 billion.
The other aspect—which is not addressed in the report—is the factor of cosmic radiation, and the fact that a human being could not withstand the extended duration of a Mars journey with the slower speed to which chemical propulsion is limited, making more energy-dense propulsion systems a necessity.
The final chapter of the report, Mission Applications, looks beyond simple space transport, to what might be considered the creation of a nuclear space industry: If a nuclear electric propulsion or nuclear thermal propulsion system is successfully developed for a crewed Mars mission, it will also be able to support the accomplishment of additional space missions. Separately, the Department of Energy and the Department of Defense are developing small nuclear fission systems for terrestrial applications. “These programs are expected to precede the baseline Mars mission and, if planned synergistically, may provide space nuclear propulsion technology advancement.”
The Space Nuclear Propulsion Technologies Committee was created in 2020, making this report an echo of the Trump-era rejuvenation of the U.S. commitment to human extraterrestrial exploration. If a manned mission to Mars is the goal of policymakers and scientists, the Biden administration will heed the Academy’s report.