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.
These cosmic ray particles can slam into molecules that make up the Earth's atmosphere, creating showers of particles.
Many of the cosmic ray particles or these "daughter" particles they create are caught in the Van Allen belts, doughnut-shaped regions where the Earth's magnetic field traps them.
Among Pamela's goals was to specifically look for small numbers of antimatter particles among the far more abundant normal matter particles such as protons and the nuclei of helium atoms.
Link thanks to haikujaguar
This entry was posted at http://nancylebov.dreamwidth.org/493422.html. Comments are welcome here or there. comments so far on that entry.