Eleven neutrinos were detected by the Kamioka water Cerenkov detector in Japan, following the explosion of supernova SN1987a. The Kamioka detector had a fiducial mass of 1000 metric tonnes. How many human beings, therefore, actually 'saw' the explosion of SN1987a

Hint - consider the structure of the human eye.

What do YOU think ?
While we're happy to HELP we won't do all the work for you.
Show us what you have done and where you are having problems..