Draw a one centimetre square on your finger & hold it towards the Sun 👆

Now consider that some 60 billion neutrinos hit it every second, created by nuclear fusion in the solar core 500 seconds ago 🙀

Even if it’s nighttime & your finger has to point down through Earth’s surface – they don’t care 🙃

But if it makes you feel better, there are only about 2 solar neutrinos in each cubic centimetre of you at any given instant 🤷‍♂️

Well, plus another 300 from the Big Bang 😬

#Astrodon #BigNumberology

@markmccaughrean

How are you defining "instant"? Planck time? Something longer?

@atatassault Infinitesimal. Simple enough calculation: divide the number of neutrinos incident on a square centimetre per second by the speed at which they transit a centimetre (just below the speed of light for neutrinos) to calculate to get the number in a cubic centimetre at any given moment in time aka the volume density of them.