4 ms·
In all seriousness, I found myself wondering about those numbers before; but consider that there's on the order of 10^27 atoms in your body. So, if we assume a
by lookatme 5y ago
In all seriousness, I found myself wondering about those numbers before; but consider that there's on the order of 10^27 atoms in your body. So, if we assume a trillion neutrinos in your body, that indicates that for each neutrino in your body, there are 10^15 atoms - that's one part per quadrillion! A machine capable of detecting neutrinos in your body would need to be _unimaginably_ sensitive, before even considering the intrinsic difficulty in detecting them due to low mass and neutral charge.
- jiggawatts 5y agoLook at it this way: Solar neutrinos carry away approximately 1% of the total fusion power output of the Sun. This works out to about 14 Watts per square meter at the distance of the Earth. The area of a human adult body front-on is about a square meter. It's pretty easy to detect 14 W of typical forms of radiation at those scales! If it were light, it would be equivalent to the light put out by something like a laptop screen, spread out just a bit. You can see something like that with your eyes from a kilometer away!
- JProthero 5y agoThis is a great analogy, I'd never seen it translated into tangible terms like that before. I remember reading that, at close enough range, the neutrino emissions from a supernova would be intense enough to be dangerous to structures made of ordinary matter, despite the weakness of their interactions, and that they would reach an observer earlier than other forms of radiation due to their ability to escape the collapsing star relatively unimpeded. Neutrinos would be the least of your problems if you were the observer of course. As I was trying to find a source for this, I discovered there is a unit [1] for the amount of energy released by a supernova called the Foe, which seems apt (it's an acronym derived from 'ten to the power of Fifty-One-Ergs'). [1] https://en.wikipedia.org/wiki/Foe_(unit) https://en.wikipedia.org/wiki/Foe_(unit)