What I’m thinking about.

Light from a supernova arrived at Earth in 1987. Along with that light there was a burst of neutrinos. Neutrinos usually interact with other matter so weakly that a block of lead a light-year thick would only stop about half of the neutrinos passing through it.

There are scientific instruments built to detect neutrinos and they are made of ENORMOUS pools of ultra-pure water, deep underground with thousands upon thousands of detectors. Every so often, a neutrino interacts with a proton in a molecule of water, it releases a bit of energy which the detector can detect. Even these only “see” a few neutrinos every few hours.

But on that day in 1987 there were so many neutrinos released that there was a person, somewhere on the planet that had their eyes closed at just the right time. And at that time they saw a little burst of light, and that light was one neutrino interacting with one of the cells in their eye. That to me, is a fascinating thing to think about.

1 year ago  /  1 note