Notice the scale by zooming out ever so slightly. Also, time scale, because it happened decades ago.
This has to be the only man-made destruction that can bee seen with the naked eye from space.
No, you can see Los Angeles from space.
It was more that 50 years ago. Now...
Basically if the explosion was any bigger it would leave the atmosphere into outer space so there is no point in making it any bigger.
I also read somewhere (but can't find the link) that although the Soviet pilots had special shutters and goggles to keep the flash out, when the bomb exploded they claimed they could see their bones through their hands.
Of course, the damage from this bomb (in terms of fallout) was much less than that resulting from the Castle Bravo test.
 - http://www.youtube.com/watch?v=FGk90-zvWOo
 - http://en.wikipedia.org/wiki/Castle_Bravo
"Each B-52 can deliver a nuclear bombload of 50 megatons, equal to 16 times the total explosive force of all the bombs and shells used by all the armies in World War Two."
Looks like we still have a way to go.