Doctor has just returned most enthusiastic and confident that the little boy is as husky as his big brother. The light in his eyes discernible from here to High Hold and I could have heard his screams from here to my farm.

Coded message describing the successful Trinity Test from George L. Harrison to US Secretary of War Henry L. Stimson, 18 July 1945

The footage is black and white, and silent, but it still has the power to shock: the sudden violent flash of light, so bright that for a second or two the horizon is invisible; the massive pyrocumulus cloud rising up over the arid valley; the way the night sky seems to quiver and throb as the light from the explosion fades. ‘Mushroom cloud’ is the noun phrase of choice, but that scarcely does justice to the scale of the thing, let alone the immensity of the event. Both figuratively and literally, the Trinity Test was earth-shattering. [More here]