The copious flux of neutrinos from the Sun—two neutrinos for every helium nucleus fused from hydrogen in the Sun’s thermonuclear core—exit the Sun unfazed by the Sun itself, travel through the vacuum of space at nearly the speed of light, then pass through Earth as though it does not exist. The tally: night and day, a hundred billion neutrinos from the Sun pass through every thumbnail square of your body, every second, without a trace of interaction with your body’s atoms.
