#TBT: Gladys Owens: 'Calutron' Technician Who Changed the World

The Calutron Girls' technical contribution created a weapon which ended the war and changed the world 

Name: Gladys Owens 

DOB: 1926 

Age today: 93

From: Tennessee, USA

Area of work: Industrial Technician on the Calutron machines – Manhattan Project

What they did: 

Gladys Owens was just 19 years of age when she arrived at the town of Oak Ridge, Tennessee. Oak Ridge wasn’t on any maps and few of the people who worked there knew its true purpose.

From January to August 1945, Gladys would spend 8 months there working as a technician on the Manhattan Project. Unknown to Gladys, history would remember her as one of the “Calutron Girls” whose role, was key to the building of the first atomic bomb.

The enrichment of uranium was the one of the most challenging aspects of building the first atomic bomb.  The enrichment of uranium is the process of separating U-235, a uranium isotope at “weapons grade” which can be used for bombs and to fuel nuclear power plants, from U-238, the other main isotope.

At the time of the second world war, this process had never been conducted before to such a large scale, so the town of Oak Ridge, with 75,000 people, was built in two years to make it happen.

The main machine used to enrich uranium was an electromagnetic machine called the Calutron. To run all 1152 of these electromagnetic machines, 24 hours a day, required a very large workforce, which is where Gladys came in. A job advert called for female high school graduates to help with the project in the new town – however, because being a Caultron technician was such a difficult job, only two out of every 3000 women who applied were chosen.

Without knowing the exact purpose of her work, Gladys spent her time, as she put it, “watching meters and adjusting dials”. She knew that magnets were involved as “if you wore bobby pins to work, they’d go flying up against the wall.” Gladys remembers their introduction to the work from one of the managers, "We can train you how to do what is needed but cannot tell you what you are doing. I can only tell you that if our enemies beat us to it, God have mercy on us!"

The meters and dials that Gladys was monitoring allowed her to control the electromagnets that were vital to the operation of the Calutrons. To separate the ‘weapons grade’ U-235 from the U-238 the Calutron fired uranium ions through an electromagnetic field. The different masses of these two ions meant that, with careful control of the electromagnets, the uranium ions could be made to follow different paths and so hit different targets. The “weapons-grade” uranium could then be scraped-off and collected from its target.

To collect the maximum amount of U-235, the technicians needed to control this process with high levels of patience, precision, watchfulness, and excellent timing. Unfortunately, when the inventor of the machine, Ernest O. Lawrence, and his team found out that technicians had been hired to run their machines they complained. They were convinced that the job required scientists with PhDs, not “hillbilly girls”.

So, the company who had built the Calutrons and hired the technicians, Tennessee Eastman Corporation, decided to run a competition. The technicians were pitted against Lawrence’s team to see who could separate the most U-235 in a week. Although the technicians were probably not told about this competition, they ‘won’ easily despite the disadvantage. The “Calutron Girls” continued to run these machines successfully and efficiently until the end of the war.

On 6th August 1945 a voice shouted out into the night from the second floor of an Oak Ridge dormitory, “Uranium! Uranium! Uranium!” a word that no-one in Oak Ridge had dared to utter until that day. President Harry S. Truman had announced to the world that the US had dropped a new weapon, a uranium bomb, on the Japanese city of Hiroshima. For Gladys and the others who worked at Oak Ridge the secret of their work was out and they now knew what they had been working on.

Gladys has mixed feelings about her part in the Manhattan project. "Sometimes I'm proud of what I was involved in," she says, "and sometimes I cry about it. We changed the world".

After the war, a photo was released of Gladys at work in Oak Ridge that led to her becoming the face of the “Calutron Girls”. She went on to become an accountant and is now retired and living in Bowling Green, Kentucky.

Without them we…

Without Gladys and her fellow ‘Calutron Girls’ the war against Japan may have been prolonged as it would have taken much longer for the first atomic bomb to have been completed.

To learn more, please visit: Andy Connelly's #technicianjourney Blog


Bonus content

Listen to Ted Rockwell, a Manhattan Project Engineer, and Gladys Evans, a Calutron Technician speak about the importance of the 'Calutron Girls' to the Second World War.


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