In 1932, physicists glimpsed antimatter for the first time — a strange mirror image of regular matter with mind-bending potential. Nearly a century later, this ghostly substance could someday fuel a leap to the stars.

Researchers Sawsan Ammar Omira and Abdel Hamid Mourad from the United Arab Emirates University argue that antimatter holds promise as the ultimate energy source for deep space propulsion. If scientists can overcome the immense challenges of producing and storing antimatter, spacecraft powered by this exotic fuel could reach nearby stars within a human lifetime.

It’s the closest thing science offers to a ticket for interstellar journeys — but only if we can figure out how to produce and store antimatter on a meaningful scale.

An Explosive Potential

Antimatter, a mirror image of regular matter with opposite electric charges, was first detected in 1932 when physicist Carl David Anderson identified positrons in cosmic rays. When antimatter touches normal matter, they obliterate each other in a flash of pure energy. That energy release is immense.

Antimatter annihilation releases an astonishing energy density of 9×10¹⁶ joules per kilogram — far beyond anything chemical or nuclear fuels can provide.

For comparison, the rocket fuel used in traditional space missions produces 43 megajoules (10⁶ joules) per kilogram. Nuclear fusion, the power source of the Sun, offers about 6.4×10¹⁵ joules per kilogram. Still, antimatter blows these out of the water by at least an order of magnitude.

A single gram of antimatter annihilating with matter would unleash the same energy as the combustion of 23 Space Shuttle fuel tanks.

“This is achieved because the entire reactant masses are converted to energy,” Omira and Mourad write.

Harnessing this energy could make voyages to the outer reaches of the Solar System — or even to neighboring stars — feasible within human lifetimes. Antimatter propulsion, the researchers argue, would enable speeds that could get spacecraft to Alpha Centauri, the nearest star system (roughly 4.3 light-years away), in just a few decades.

In comparison, Voyager 1 — the most distant spacecraft ever, which recently barely crossed the threshold into interstellar space — would take over 80,000 years to make the same journey.

Even within our own solar system, the difference would be dramatic. Instead of the nine-and-a-half years NASA’s New Horizons probe took to reach Pluto, an antimatter engine could get us there in just 3.5 weeks.

Why Aren’t We There Yet?

As tantalizing as antimatter propulsion sounds, the challenges are enormous. Antimatter is incredibly scarce. It doesn’t just lie around waiting to be scooped up. Producing it is an arduous process that currently requires powerful particle accelerators.

Still, the most glaring issue is cost. CERN, the European Organization for Nuclear Research, has the world’s most advanced antimatter production facility. However, CERN is capable of making just ten nanograms of antiprotons per year. Generating a single gram of antimatter — the amount needed to test a propulsion system — would require $4 million in energy costs and enough power to supply a small city for a year (25 million kWh of energy).

Gerald Jackson, an accelerator physicist formerly with Fermilab, estimated it would cost $8 billion to build a solar power plant capable of producing 20 grams of antimatter per year. Maintaining such a facility would cost an additional $670 million annually.

And once produced, storing it is even trickier.

Antimatter can’t touch regular matter without annihilating on contact. That means it needs to be confined using magnetic or electric fields in ultra-high-vacuum environments. So far, researchers have managed to trap only a few atoms of antihydrogen for brief periods. That’s a long way from the kilograms needed to propel a starship.

“Storing solid or liquid antimatter in contact with any state of matter is impossible,” the authors explain.

The study proposes some storage solutions such as cryogenically cooled magnetic traps. In these systems, tiny pellets of frozen antihydrogen would be suspended in vacuum tunnels etched onto silicon chips. Even with these innovations, storing enough antimatter for a deep space mission remains beyond current capabilities.

A Glimpse into the Future

Despite these challenges, the researchers envision various antimatter rocket designs that could one day power interstellar travel. One promising concept is the “beam-core” rocket. In this design, antiprotons annihilate with protons, producing charged particles that are funneled out through a magnetic nozzle to generate thrust. Theoretically, this could achieve speeds up to 40% of the speed of light.

For closer-to-home missions, such as journeys within the Solar System, “plasma-core” engines could provide a more practical solution. These systems would inject antiprotons into a hydrogen plasma, creating high-temperature exhaust to propel spacecraft.

However, the authors caution that without significant advances in antimatter production, even the most optimistic scenarios remain distant.

“Although antimatter propulsion has substantial potential, its study is relatively recent, and no experimental work has been conducted yet,” they write.

Even if the propulsion technology existed today, testing it would be risky. The immense energy from antimatter annihilation could lead to catastrophic explosions if something went wrong. Steve Howe, a physicist who worked on antimatter projects with NASA, suggested the moon might be the safest place to experiment. “If something goes wrong, you melted a piece of the moon,” he said, rather than endangering Earth.

Why Pursue the Impossible?

Antimatter propulsion might sound like science fiction, but the pursuit of such ideas has driven progress in unexpected ways. Technologies developed for antimatter research have already found applications in medical imaging, such as PET scans.

And who knows? A breakthrough in particle physics, material science, or energy storage might one day turn antimatter rockets from theory into reality.

“The continuous evolution of space exploration requires us to be committed to innovate and develop enhanced propulsion systems,” Omira and Mourad write.

If humanity wants to reach beyond the Solar System, antimatter might be the only fuel that can take us there. For now, it remains a distant dream — one powered by the smallest, most powerful bursts of energy the universe can offer.

The findings were reported in the International Journal of Thermofluids.