This is not so much an April Fools joke as it is a little riddle. It connects to a current event... and to things that happened in the last century. And of course it has something to do with nuclear power.
This is a comparison between two estimated values... what are they?
Update: we have a winner! Tony scored a perfect bullseye. I'm quoting him here:
‘a’ is the number of iodine atoms that would fill the known universe, if the iodine were at ‘normal’ temperature/pressure.
the second number is the number of radioactive iodine atoms you would have needed, when Chernobyl exploded, in order to have one radioactive iodine atom left today.
An added trivia is that the estimated number of atoms in the known universe is approximately 10^80.
The upshot of all this is this: there is not a single atom of Iodine-131 released by Chernobyl in existence today. The last atom decayed in no more than 4 years after the accident.