Putting the brakes on antihydrogen

Scientists have long wondered why so little antimatter is found today in the universe. Presumably, both matter and antimatter were created in equal amounts in the Big Bang.

SELF-DESTRUCT. A tiny fireball, triggered when a drifting antihydrogen atom struck some ordinary matter, unleashes pions (yellow tracks) and gamma rays (red tracks) into surrounding detectors. ATHENA Collaboration

Researchers at the European Organization for Nuclear Research (CERN) in Geneva have now made the first slow-moving atoms of antimatter.