Scientists have a problem with cosmic rays—they produce too many muons at the Earth’s surface. Cascades of muons are byproducts of high-energy cosmic rays as they collide with nuclei in the upper atmosphere, and scientists see more muons at Earth’s surface than standard physics models predict. Scientists have a problem with cosmic rays—they produce too many muons at the Earth’s surface. Cascades of muons are byproducts of high-energy cosmic rays as they collide with nuclei in the upper atmosphere, and scientists see more muons at Earth’s surface than standard physics models predict. General Physics Phys.org – latest science and technology news stories