A friend asks if the Nagasaki was visible, as reported in "The Empire of
the Sun".
I calculated the distance from the top of the fireball to the horizon
(~70 kM) and found it ~ < 1/10 th the distance to Shanghai. (800 Km)
Using the same data at Frenchman Flat, I get Vegas as about twice.
Vegans saw a glow from the tests.