In the past hour, there has been a rare (for Belfast, that is) storm, with impressive, deep rumbles of thunder, flashes of sheet lightning, and minutes later a torrential downpour of hail.
I stood outside while the hail was coming down, and feared for the flimsy patio roof above my head, in the way you would feel a pleasing terror at a horror movie. When the thunder-flashes came, every few minutes, it was as if you’d blinked when you hadn’t; a tic in the visual field, nothing more. Which was dispelled when the rumbles arrived. Then I read this:
The speed of sound in air is approximately 344 m/s or 1130 feet per second or 762 mph. The speed of light can be assumed to be infinite in this calculation because one must know that there has been a lightning strike before starting counting. Therefore, the lightning is approximately one kilometer distant for every 2.9 seconds (or one mile for every 4.6 seconds). In the same five seconds the light could have circled the globe 37 times.
Ahhh. The world we live in.