How Antimatter Spacecraft Will Work

By: Kevin Bonsor & Yara Simón  | 
Mars with a partial eclipse
Approximately 10 grams of antiprotons would be enough fuel to send a manned spacecraft to Mars in one month. Today, it takes a little less than a year for an unmanned spacecraft to reach Mars. Adastra / Getty Images

"Engineering, stand by for warp drive." With that command, the "Star Trek" crew of the U.S.S. Enterprise prepared to hurl the spaceship through the cosmos at superluminal speeds.

Warp drive is one of those science-fiction technologies, like teleportation and time travel, that have some scientific basis. We just haven't achieved it yet. However, scientists are working on developing an interstellar spacecraft engine that is similar to the antimatter engine of the Enterprise.


Antimatter spacecraft like this one could someday shorten a trip to Mars from 11 months to one month. Check out current spaceflight technology in these pictures of space shuttles.
Photo courtesy NASA

­No engine is likely to generate superluminal speeds; the laws of physics prevent us from doing that, but we will be able to go many times faster than our current propulsion methods allow. A matter-antimatter engine will take us far beyond our solar system and let us reach nearby stars in a fraction of the time it would take a spacecraft propelled by a liquid-hydrogen engine, like the one used in space shuttles.

It's like the difference between driving an Indy race car and a 1971 Ford Pinto: In the Pinto, you'll eventually get to the finish line, but it will take 10 times longer than in the Indy car.

Let's peer a few decades into the future of space travel to look at an antimatter spacecraft and find out what antimatter actually is and how we might use it for an advanced propulsion system.


What is Antimatter?

In this composite image of the Crab Nebula, matter and antimatter are propelled nearly to the speed of light by the Crab pulsar. The images came from NASA's Chandra X-ray Observatory and the Hubble Space Telescope.
Photo by NASA/Getty Images

This isn't a trick question. Antimatter is exactly what you might think it is — the opposite of normal matter, of which the majority of our universe is made. At one point, scientists considered the presence of antimatter in our universe as only theoretical.

British physicist Paul Dirac helped change our understanding of antimatter.


In 1928, he revised Einstein's famous equation E = mc². Dirac said that Einstein didn't consider that the "m" in the equation — mass — could have negative energy as well as positive energy. Dirac's equation (E = + or - mc²) allowed for the existence of anti-particles in our universe. Scientists have since proven that several anti-particles exist.

Antimatter Particles At Work

These anti-particles are, literally, mirror images of normal matter. Each anti-particle has the same mass as its corresponding particle, but the electrical charges are reversed. Here are some antimatter discoveries of the 20th century:

  • Positrons: Electrons with a positive instead of a negative charge. Discovered by Carl Anderson in 1932, positrons were the first evidence that antimatter existed.
  • Anti-protons: Protons that have a negative instead of the usual positive charge. In 1955, researchers at the Berkeley Bevatron produced an antiproton.
  • Anti-atoms: Pairing together positrons and antiprotons, scientists at CERN, the European Organization for Nuclear Research, created the first anti-atom. Nine anti-hydrogen atoms were created, each lasting only 40 nanoseconds. As of 1998, CERN researchers were pushing the production of anti-hydrogen atoms to 2,000 per hour.

When antimatter comes into contact with normal matter, these equal but opposite particles collide to produce an explosion emitting pure radiation, which travels out of the point of the explosion at the speed of light. Both particles that created the explosion are completely annihilated, leaving behind other subatomic particles.


The explosion that occurs when matter and antimatter meet transfers the entire mass of both objects into energy. Scientists believe that this energy is more powerful than any that can be generated by other propulsion methods.

Antimatter in the Universe

Gamma rays and cosmic rays are high-energy particles and radiation that originate from various sources in the universe, such as supernovae, black holes and even the Big Bang itself. Scientists theorize that antimatter should be as abundant as ordinary matter because of the Big Bang, but it's scarcely observed in our universe.


The Role of Particle Detectors

A particle detector is an essential tool in the field of particle physics. They enable scientists to identify and study subatomic particles, including those made of antimatter, as they interact with matter. By capturing and analyzing particle interactions, detectors help scientists understand fundamental particle properties and investigate the universe's origins.


So Why No Matter-Antimatter Reaction Engine?

The problem with developing antimatter propulsion is that there is a lack of antimatter existing in the universe. If there were equal amounts of matter and antimatter, we would likely see these reactions around us. Since antimatter doesn't exist around us, we don't see the light that would result from it colliding with matter.

It is possible that particles outnumbered anti-particles at the time of the Big Bang. As stated above, the collision of particles and anti-particles destroys both. And because there may have been more particles in the universe to start with, those are all that's left. There may be no naturally existing anti-particles in our universe today.


However, scientists discovered a possible deposit of antimatter near the center of the galaxy in 1977. If that does exist, it would mean that antimatter exists naturally, and the need for antimatter production would no longer be necessary.

For now, we have to create all the antimatter ourselves. Luckily, there is technology available to create antimatter through the use of high-energy particle colliders, also called "atom smashers."

Atom smashers, like CERN, are large tunnels lined with powerful supermagnets that circle around to propel atoms at near-light speeds. When an atom is sent through this accelerator, it slams into a target, creating particles. Some of these particles are antiparticles that are separated out by the magnetic field.

These high-energy particle accelerators only produce one or two picograms of antiprotons each year. A picogram is a trillionth of a gram. All of the antiprotons produced at CERN in one year would be enough to light a 100-watt electric light bulb for three seconds. It will take tons of antiprotons to travel to interstellar destinations.


Matter-Antimatter Engine

Antimatter spacecraft like the one in this artist concept could carry us beyond the solar system at amazing speeds.
Photo courtesy Laboratory for Energetic Particle Science at Penn State University

NASA is possibly only a few decades away from developing an antimatter spacecraft that would cut fuel costs to a fraction of what they are today. In October 2000, NASA scientists announced early designs for an antimatter engine that could generate enormous thrust with only small amounts of antimatter fueling it. The amount of antimatter needed to supply the engine for a one-year trip to Mars could be as little as a millionth of a gram, according to a report in that month's issue of Journal of Propulsion and Power.

Matter-antimatter propulsion will be the most efficient propulsion ever developed because 100 percent of the mass of the matter and antimatter are converted into energy. When matter and antimatter collide, the energy released by their annihilation releases about 10 billion times the energy that chemical energy such as hydrogen and oxygen combustion, the kind used by the space shuttle, releases.


Matter-antimatter reactions are 1,000 times more powerful than the nuclear fission produced in nuclear power plants and 300 times more powerful than nuclear fusion energy. So matter-antimatter engines have the potential to take us farther with less fuel. The problem is creating and storing the antimatter. There are three main components to a matter-antimatter engine:

  • Magnetic storage rings: Antimatter must remain separate from normal matter so storage rings with magnetic fields can move the antimatter around the ring until it is needed to create energy.
  • Feed system: When the spacecraft needs more power, the antimatter will be released to collide with a target of matter, which releases energy.
  • Magnetic rocket nozzle thruster: Like a particle collider on Earth, a long, magnetic nozzle will move the energy created by the matter-antimatter through a thruster.
The storage rings on the spacecraft will hold the antimatter.
Photo courtesy Laboratory for Energetic Particle Science at Penn State University

Approximately 10 grams of antiprotons would be enough fuel to send a manned spacecraft to Mars in one month. Today, it takes a little less than a year for an unmanned spacecraft to reach Mars. In 1996, the Mars Global Surveyor took 11 months to arrive at Mars.

Scientists believe that the speed of a matter-antimatter powered spacecraft would allow man to go where no man has gone before in space. It would be possible to make trips to Jupiter and even beyond the heliopause, the point at which the sun's radiation ends. But it will still be a long time before astronauts are asking their starship's helmsman to take them to warp speed.

This article was updated in conjunction with AI technology, then fact-checked and edited by a HowStuffWorks editor.