This article is unfortunately murky. It’s confusing to state that accelerating charged particles to high speeds “therefore” produces cosmic rays. And what “charged particles”? Is the “energized” gas in fact “ionized”? “Energized” is too general a word. Finally, why are high-speed particles more easily compressed than slower-moving material?

Fredric Blum
Merion, Pa.

“Energized” means that the charged particles, existing electrons and ions, are speeded up to energies high enough to qualify as cosmic rays.