By Kurtis Archer | 2026-01-22

Travel to worlds beyond the solar system would require the development of a fundamentally different type of propulsion system, with physicists suggesting that antimatter is the most energetic fuel source for deep space exploration.

Mass converts directly into energy, per Albert Einstein’s E = mc^2 formula. When antimatter and matter particles touch, they annihilate each other in a flash of energy. This process releases an energy density roughly 300 times that of nuclear fusion, and 10 billion times as powerful as chemical combustion.

"This is achieved because the entire reactant masses are converted to energy," United Arab Emirates University researchers Sawsan Ammar Omira and Abdel Hamid Mourad wrote in the International Journal of Thermofluids last January.

"The energy that this reaction releases is ridiculously giant and is higher than any other reaction known in physics," they note, in a paper they co-authored on the potential for the use of antimatter as fuel for interstellar travel.

"Antimatter propulsion is a groundbreaking technology with potential to transform space exploration, enabling travel to distant locations once deemed impossible," the study says.

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

According to the researchers, the first step would be "establishing a stable antimatter production line with much larger storage capacities" -- something humans have not yet been able to achieve.

"Antihydrogen is the simplest pure antimatter atom," they explain. "Its stability, long-term storage capability, and simplicity of production give it the potential to scale up its production and storage capacities."

Creating antimatter thrust

The necessary technologies are unlikely to be developed soon, as serious challenges exist.

Facilities with powerful particle accelerators such as the European Organization for Nuclear Research (CERN) currently manage antimatter production that is limited to thousands of atoms per day, according to Universe Today.

Production efficiency currently stands at around 0.000001%. But a gram of antimatter would need to be generated to test a propulsion system.

Accelerator physicist Gerald Jackson, formerly with Fermilab, estimated that a solar power plant capable of producing 20 grams of antimatter per year would cost $8 billion to build and $670 million per year to maintain.

Physicist Steve Howe, who worked on antimatter projects with NASA, has said he believes that testing antimatter for these types of technologies should be done on the moon, due to the potential danger of such experiments.

Another challenge is that antimatter is the most expensive substance on Earth -- currently worth $62.5 trillion per gram, according to Science to Go.

Antiproton-nucleon annihilation and positron-electron annihilation are two promising antimatter reactions for future deep space missions, per Omira and Mourad.

These reactions are stable and offer a substantial energy release, with propulsion reaching up to 20 million m/s, which would theoretically place interstellar travel within the timeframe of a human’s lifespan.

Antiprotons and positrons exhibit the necessary stability to be stored safely for extended periods of time, needed for interstellar travel.

Antimatter use and storage

Since antimatter annihilates with matter instantly, complex electromagnetic storage systems would be needed.

"Storing solid or liquid antimatter in contact with any state of matter is impossible," the researchers note, suggesting storage solutions such as cryogenically cooled magnetic traps.

These traps would have tiny pellets of frozen antihydrogen suspended in vacuum tunnels carved into silicone chips. But even with ideas like this, antimatter storage for deep space missions remains beyond current technology.

Designing engines that can handle this type of fuel is another challenge.

Simple approaches to the idea use antimatter to heat a refractory block that propellant flows through, reaching a performance not unlike nuclear thermal rockets and without needing an onboard reactor.

A promising concept is the "beam-core" rocket in which protons annihilate with antiprotons, producing charged particles that are fed out through a magnetic nozzle to create thrust.

This system could theoretically achieve up to 40% the speed of light.

For trips within the solar system, "plasma-core" engines could inject antiprotons into a hydrogen plasma, which would create high-temperature exhaust for thrust.

More complex designs combine antimatter with uranium-238, which is the naturally occurring form of uranium.

Fission can be triggered in U-238 by antiprotons, producing particles that are highly charged and output energy into the exhaust stream much more efficiently than gamma rays alone.

Fuel for the future?

These hurdles aside, antimatter propulsion could enable a spacecraft to reach Alpha Centauri, the nearest star system about 4.3 light-years away, in a matter of decades, as opposed to millennia.

For comparison, Voyager 1, the farthest spacecraft from Earth, would take over 80,000 years to make that journey, per ZME Science.

Antimatter technology would be revolutionary for space travel even within Earth’s solar system.

NASA’s New Horizons probe reached Pluto after a 9.5-year journey, but an antimatter engine may have enabled it to reach the dwarf planet in 3.5 weeks.

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

"If enough funding and efforts were devoted to further research on this technology and a solution to utilize annihilation’s energy was found, then interstellar and human interplanetary missions wouldn’t be deemed impossible."