The visible light penetrating my goggles increased, and the heat on my back grew more intense. I squirmed to distribute the heat from my side to my back.

About 30 or 40 seconds after detonation, I took off the goggles and watched the angry violet-red and brown cloud from the fireball.

As the rising cloud started to form a mushroom cap, I waited for the shock wave to arrive. In the distance, I could see a long vertical shadow approaching. I instinctively opened my mouth and moved my jaw side to side to equalize pressure difference across my eardrums, closed my eyes and put my hands over my ears.

Pow!

It hit me like a full body slap, knocking me back. I opened my eyes to see another shadow approaching from a slightly different direction. Over the next few seconds, I felt several smaller blows created by reflections of the pressure wave off distant islands.