The find, described in Astrophysical Journal Letters, confirms theoretical work that predicted the Earth's magnetic field could trap antimatter.
The team says a small number of antiprotons lie between the Van Allen belts of trapped "normal" matter.
The researchers say there may be enough to implement a scheme using antimatter to fuel future spacecraft.
The antiprotons were spotted by the Pamela satellite (an acronym for Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) - launched in 2006 to study the nature of high-energy particles from the Sun and from beyond our Solar System - so-called cosmic rays.
Pamela craft discovers antimatter belt around Earth
Posted on Sunday, August 07 2011 @ 22:20 CEST by Thomas De Maesschalck
BBC News reports Pamela (Payload for Antimatter Matter Exploration and Light-nuclei Astrophysics) has confirmed the existence of a thin band of antiprotons around our planet: