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Atomic rockets are back

While the current Oppenheimer blockbuster film focused on the destructive power of nuclear weapons, more peaceful uses of atomic propulsion for space exploration are now gaining once again momentum. ROB COPPINGER reports.

Nuclear fission and fusion power propulsion are under investigation in Europe and the US with an in-space engine demonstration planned by 2027 — with the news last month that Lockheed Martin had been selected to develop a nuclear thermal propulsion system for DARPA’s DRACO programme (see below).

Nuclear propulsion is attractive as it is far more efficient and powerful than conventional chemical rocket engines – with nuclear thermal propulsion (NTP) having twice the propellant efficiency of chemical rockets. SpaceX plans to use its Starship Heavy rocket, propelled by liquid oxygen and methane, to take Elon Musk’s colonists to Mars. NASA’s decades of research have also concluded that NTP is the best choice for crewed missions to the red planet with its Human Exploration of Mars Design Reference Mission 5.0, published in 2009, making clear NTP’s advantages. With NTP, a propellant, liquid hydrogen, is propelled by the heat from a nuclear reactor. It offers a high thrust-to-weight ratio around 10,000 times greater than nuclear electric propulsion (NEP) and two-to-five times greater specific impulse than in-space chemical propulsion.

Bigger and better quantum computers possible with new ion trap, dubbed the Enchilada

Another concern was the dissipation of electrical power on the Enchilada Trap, which could generate significant heat, leading to increased outgassing from surfaces, a higher risk of electrical breakdown and elevated levels of electrical field noise. To address this issue, production specialists designed new microscopic features to reduce the capacitance of certain electrodes.

“Our team is always looking ahead,” said Sandia’s Zach Meinelt, the lead integrator on the project. “We collaborate with scientists and engineers to learn about the kind of technology, features and performance improvements they will need in the coming years. We then design and fabricate traps to meet those requirements and constantly seek ways to further improve.”

Sandia National Laboratories is a multimission laboratory operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Administration. Sandia Labs has major research and development responsibilities in nuclear deterrence, global security, defense, energy technologies and economic competitiveness, with main facilities in Albuquerque, New Mexico, and Livermore, California.

SHINE Technologies

Cherenkov radiation achieved in faster than light reactions by SHINE.


SHINE has demonstrated clearly visible Cherenkov radiation produced by fusion for what is believed to be the first time in history. This visible evidence provides further proof that fusion can produce neutrons on par with some nuclear fission reactors.

Nuclear Fusion Heats Up

The observation of self-heating in magnetically confined plasmas represents a milestone on the road to fusion reactors based on such plasmas.

A fusion reactor would generate electricity using the energy released by nuclear-fusion reactions occurring in a plasma. A key step in the race toward realizing the dream of such a reactor is the creation of a burning plasma—one in which the fusion reactions themselves supply most of the heating needed to keep the plasma at fusion-relevant temperatures. This step has recently been demonstrated for inertially confined plasmas [1, 2] (see Research News: Ignition First in a Fusion Reaction) but has so far remained elusive for magnetically confined ones. This goal could now be within reach thanks to direct evidence for fusion-induced heating of electrons in magnetically confined plasmas obtained by Vasily Kiptily and colleagues at the UK-based Joint European Torus (JET) facility [3].

The fusion of two heavy hydrogen isotopes—deuterium (D) and tritium (T)—presents the most promising path to a fusion reactor, both because of the relative ease in getting these isotopes to fuse and because of the large amount of energy released in each reaction. When D and T fuse, an alpha particle (a helium-4 nucleus) and a neutron are generated, carrying the released energy in the form of kinetic energy. The goal of achieving energy production from controlled fusion on Earth relies on the created alpha particles remaining in the plasma and heating the fusion fuel to keep the reactions going, while the kinetic energy of neutrons escaping the plasma is converted to electrical energy.

NASA’s Building a Nuclear Rocket That Would Get Us to Mars in Just 6 Weeks

Deep space is a hostile environment for humans, which makes the long journey to Mars a serious stumbling block for manned missions. A nuclear-powered rocket could slash the journey time, and NASA has announced plans to test the technology by 2027 at the latest.

Most spacecraft to date have used chemical rockets packed with fuel and oxidizer, which rely on combustion to propel them through space. A nuclear-powered rocket would instead use a fission reactor to heat liquid hydrogen to very high temperatures and then blast it out the back of the spacecraft.

These kinds of engines could be up to three times more efficient than those in conventional rockets, and could cut the time to transit from Earth to Mars from roughly seven months to as little as six weeks. NASA has teamed up with DARPA to make the idea a reality, signing a deal with defense contractor Lockheed Martin to launch a working prototype into space as early as 2025.

US scientists achieve net energy gain for second time in a fusion reaction

US scientists have achieved net energy gain in a nuclear fusion reaction for the second time since a historic breakthrough in December last year in the quest to find a near-limitless, safe and clean source of energy.

Scientists at the California-based Lawrence Livermore National Laboratory repeated the breakthrough in an experiment in the National Ignition Facility (NIF) on 30 July that produced a higher energy yield than in December, a Lawrence Livermore spokesperson said.