One of the military witnesses, Major General Thomas Farrell, clearly in awe of the moment, desperately tried to find the right words: “The effects could well be called unprecedented, magnificent, beautiful, stupendous, and terrifying,” he wrote in his report to Groves. “The lighting effects beggared description… it was golden, purple, violet, grey and blue…” He continued in a like vein for some time. The more phlegmatic Groves replied with a single word: “noted.”
Other observers and correspondents have been using equally florid language to describe the bubbling horror of nuclear explosions ever since. Those without quite the same literary bent, or foreknowledge of what to expect, reacted rather differently. A humble G.I. fled in terror from his dugout screaming: “The long-hairs have let it get away from them…” Scientists, technicians and other observers displayed varying degrees of fear and elation. As the shock wave rolled over their heads, many sprang from their bunkers and performed an impromptu conga beneath the spreading effulgence of the world’s first mushroom cloud.
Others far away also noted the momentous event. The flash of light was seen in Santa Fe, Albuquerque, Silver City and El Paso. It was so intense a blind girl 50 miles away asked, “What was that?”
With secrecy still paramount, Groves issued a cover story to stop word of the new super-weapon reaching the outside world. The local Santa Fe radio announced there had been an explosion in an ammunitions dump; for chance observers further away, army intelligence prepared stories blaming the strange event on an earthquake or a plane crash. Groves manage to insert an item in the local paper about a fictitious rail passenger who described “the biggest firework display I have ever seen…”
But at Los Alamos, and very much against the wishes of Groves, there was uninhibited joy. As news of the success of Trinity started to filter through, people took to the streets gathering excitedly; when it was confirmed, the dancing and cheering began. A group of technicians’ wives went out bashing pots and kettles; people sat on the hoods of cars drinking and laughing, while scores formed congas that snaked in and out of the houses. Parties sprang up all over town.
Later drunken revellers stood in swaying groups as they waited for the buses carrying the dishevelled scientists to return home from Alamogordo. When they arrived they were so exhausted many wished for nothing but a shower and bed. But others simply couldn’t sleep. They barged into communal areas wearing huge grins and flashing ‘V’ for victory signs.
The mood of euphoria was replaced by more sober thoughts as the sheer scale of the explosion began to sink in. Early reports said it was equivalent to 20,000 tons of TNT and that it had caused a vast black cloud of radioactive fallout. This had drifted over the desert mesas and contaminated huge areas up to 100 miles away. The silent aftermath of the detonation was said to be punctuated by staccato gunfire as specially trained GIs fanned out into the desert to destroy a herd of antelope driven crazy by radiation burns.
Penney was one of the first to be taken into the still smoking blast area to check on vital monitoring instruments he had set up at varying distances from ground zero. Groves marvelled at the simplicity of some of the equipment the scientist had devised: wooden boxes with different sized holes drilled into them and covered with paper membranes; toothpaste tubes filled with differing amounts of water. From the way the membranes had been punctured, and the toothpaste tubes bent, Penney could calculate the force of blast wave and even its shape. His calculations were often more accurate than the expensive electronic equipment devised by American scientists.
With the success of the Trinity explosion, the military planners got down to deciding which of the cities on the Japanese mainland should join Hiroshima as the luckless recipient of this new and terrifying weapon. There was never any doubt in their minds that the A-bomb should be used on Japan. Reports of the fanatical and suicidal defence by Japanese soldiers on Iwo Jima and Okinawa were convincing proof of the level of opposition the Allies would be likely to face in the event of an attack on the mainland. Hundreds of thousands of American lives would be lost before Japan surrendered.
The use of the atomic bomb to subjugate Japan quickly and with a minimal loss of American lives was therefore a no-brainer for people like Groves. But by this time the tide of war had turned against Germany and many scientists, who had joined the Manhattan Project because of their fear of the Nazis, were uncomfortable about its use on Japan. To avoid huge loss of civilian life, some suggested the bomb should be exploded harmlessly over Tokyo Bay to demonstrate its power and force Japan to the negotiating table. This was dismissed by President Truman who believed Japan would never capitulate unless forced to. He told the hierarchy at Los Alamos to “get on with it.”
Groves and his security detail decided to isolate what he called the ‘dissidents’ and excluded many of the scientists from involvement in further development. Penney was most definitely on the side of Groves and appears to have been part of what was called the ‘goon squad’, a group of scientists and security staff charged with investigating the backgrounds of those who objected to using the bomb.
Michael Moore marked down early on as a possible dissident said: “It’s true I wasn’t very happy about using the atom bomb on a city of defenceless people, and I remember signing a petition got up by some of the other scientists. Even though I wasn’t a very important cog in the scheme of things, the goon squad arrived and put the thumb-screws on me to remove my signature. I refused. I argued that my primary objection was on moral grounds because I was horrified with what the bomb would do to people. But I was also very concerned about the long-term effects. The dangers from fall-out were very well known, even then, but that seemed to have no effect on plans for further bomb development which I knew were in the pipeline.”
Moore was later sent back to Liverpool, where he was told his skills as a metallurgist were urgently required. It was a far less secretive task than his work in Berkerley and Los Alamos, and Moore always felt he had been sidelined. He was effectively barred from all future work on atomic projects.
It later turned out the ‘goon squads’ missed their targets completely. Neither Rotblat nor Moore was a security risk. That dubious honour fell to Klaus Fuchs one of of Los Alamos’s most trusted scientists, who succeeded in handing Stalin the complete blueprints of the atomic bomb on a plate.
The plan to bomb Japan went ahead and Penney was set the task of deciding the height at which the bomb should be exploded to ensure maximum damage. Working alongside him was another British scientist and friend, Ernest Titterton. The two had been close ever since their university days and Penney was said to be mortified when Titterton’s wife, who also worked at Los Alamos, gave birth to a child with spina bifida. Radiation exposure was accepted as being the cause, and it had a sobering effect on those enthusiastic about using the bomb. Penney never said what his thoughts were, but even though he was said to ‘love children more than adults’, he never had any more children, even though he remarried soon after returning from Los Alamos.
Penney as one of the elite of Los Alamos, joined 51 scientists, engineers and weapons experts who one morning was suddenly not there anymore. One by one they had left in the night; they didn’t even bother to pack. Those left behind of course could guess what had happened: they were the ones chosen to complete the final phase of their work at Los Alamos.