Antimatter traveled by truck for the first time

Scientists at CERN transported 92 antiprotons eight kilometers across the lab grounds

A truck with a banner reading "Antimatter in motion."

Scientists at CERN transported antimatter in a truck (shown) for the first time.

CERN

Special delivery: antimatter.

Scientists have completed the first-ever transport of antimatter by truck. On March 24, researchers carried antiprotons, the negatively charged counterparts of protons, inside a magnetic trap on a truck. The particles, created at the European particle physics laboratory CERN in Geneva, traveled about eight kilometers to another site within the lab before the trap was delivered, contents intact.

That’s quite a feat because antimatter annihilates when it comes into contact with matter. So the antiprotons were corralled with electromagnetic fields to prevent them from banging into the walls of their container while trucking along.

Scientific equipment is lowered by crane into the back of a truck, while people in hard hats look on.
The BASE-STEP project’s antimatter trap (shown) was loaded onto a truck before an eight-kilometer trip. Magnetic fields prevent the particles from slamming into the walls of the trap and annihilating as the truck jiggles.CERN

The demonstration, which followed a test with protons in 2024, is part of an effort called BASE-STEP. Eventually, scientists hope to use BASE-STEP’s technology to bring antiprotons from CERN to facilities around Europe. There, scientists will build carefully controlled experiments, free from the stray magnetic fields pervading the accelerator facility at CERN that produced the antimatter.

Those careful experiments could help scientists better understand why matter is common in the universe, while antimatter is rare. It’s thought that the Big Bang produced matter and antimatter in equal parts. Something must have tipped the balance in matter’s favor. So scientists have been carefully scrutinizing antimatter particles’ properties, such as their charge-to-mass ratios, atomic energy levels, response to gravity and the like, to search for any discrepancies with matter.

The new portability demonstration is the first step toward antimatter experiments of a new level of quality, physicist Stefan Ulmer of RIKEN in Wako, Japan, said at a news conference announcing the achievement. “This is a starting point of a really exciting journey.”

Senior physics writer Emily Conover has a Ph.D. in physics from the University of Chicago. She is a two-time winner of the D.C. Science Writers’ Association Newsbrief award and a winner of the Acoustical Society of America’s Science Communication Award.