[ramblenode]

This sort of order of magnitude estimation is essentially a Fermi question [1]. Anyone interested in these might also check out problems from the high school Science Olympiad event of the same name. Here is a page which links to some past tests: [2]

[1] https://en.wikipedia.org/wiki/Fermi_problem

[2] https://www.sciencenc.com/resources/high-school/fermi-questi...