The Trinity Test

     Fat Man was mounted on a hundred foot tower ten miles from base camp, and the site was surrounded by bunkers for observation, the closest person five miles away. At 5:09 the first atomic bomb exploded. Even from twenty miles away observers felt the heat of the explosion and saw a gigantic flash light up the night sky. The is an observatiuon of Enrico Fermi describing the blast:
"My first impression of the explosion was the very intense flash of light, and a sensation of heat on the parts of my body that were exposed. Although I did not look directly towards the object, I had the impression that suddenly the countryside became brighter than in full daylight... After a few seconds the rising flames lost their brightness and appeared as a huge pillar of smoke with an expanded head like a gigantic mushroom that rose rapidly beyond the clouds probably to a hight of 30,000 feet... I estimated to correspond to the blast that would be produced by 10,000 tons of T.N.T."
This was Maurice M. Shapiro's description of the explosion:
"At the time of the initial flash of light my eyes were not protected, and I was momentarily blinded, much as one would be in emerging suddenly from a dark room into bright sunlight. After a couple of seconds I regained sufficient sight to see the entire sky (in the direction of Trinity) aglow with an orange hue. This glow disappeared after a second or two, and then I saw a column of dark gases rising toward the overhanging clouds. Several people near me commented on the violet color of the cloud of gas, but I observed no such color, presumably because of the initial effect on my eyes. I estimated the width (or diameter) of the column of gas as roughly 1/5 mile. After a few minutes this column rose to a height which I judged to be 8 or 10 miles high, and then it spread laterally. There were a few small puffs of white vapor, which I interpreted as arising from a "cloud-chamber effect" (supersaturation followed by condensation of moisture)."
The blast vaporized the steel tower that held the bomb and created a crater 1,200 feet across. The sands around Ground Zero were fused into a green glass called trinite. The blast was also heard from 100 miles away and the smoke visible from 180 miles. Finally the years of hard work had paid off and altered the scientific world forever.