[Wonder Warthog]

"could someone define a cosmic ray"

"A stream of ionizing radiation of extraterrestrial origin, consisting chiefly of protons, alpha particles, and other atomic nuclei but including some high-energy electrons, that enters the atmosphere, collides with atomic nuclei, and produces secondary radiation, principally pions, muons, electrons, and gamma rays."

That secondary radiation is what causes charges to form in the atmosphere which serve as nucleation sites for water droplets, and the increased cloud cover.

[mamalujo]

thanks

I thought the article said we had decreased cloud cover

[Erasmus]

In other words, the upper atmosphere is a gigantic cloud chamber.

Or, a cloud chamber is a tiny version of the upper atmosphere.

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