If You Liked ‘Hidden Figures,’ Watch This Documentary Next

Top Secret Rosies highlights female mathematicians creating ballistics programs for World War II

28 February 2017

On the heels of the award-winning Hidden Figures movie, I thought it a good time to remind readers of Top Secret Rosies: The Female Computers of WWII, a documentary released in 2010. I recently watched the documentary, which is about the 80 women who pitched in as “human computers” on a secret U.S. military program [watch the trailer below]    . Working at the University of Pennsylvania’s Moore School of Electrical Engineering, in Philadelphia, the women calculated trajectories of artillery shells and other ammunition for soldiers. Filmmaker LeeAnn Erickson interviewed four of the women.

The documentary also covers how the ballistics technology led to the development of the world’s first electronic computer, the ENIAC, an IEEE Milestone​. Six of the women working on the ballistics program were tapped to become ENIAC’s first programmers: Kathleen McNulty Mauchly Antonelli, Jean Jennings Bartik, Frances Snyder Holberton, Marlyn Wescoff Meltzer, Frances Bilas Spence and Ruth Lichterman Teitelbaum. Programmers didn’t exist before the 1930s, because computers didn’t exist.

Like the mathematicians’ efforts featured in Hidden Figures, the work of the top-secret Rosies in the ballistics program and of the ENIAC programmers was not publicly acknowledged for decades.


The term “Rosies” comes from the Rosie the riveter character the U.S. government featured in advertisements recruiting female workers for jobs in the defense industry during World War II. Rosie made the weapons, but the human computers made them more accurate.

Beginning in 1942, the U.S. Department of Defense began recruiting young women in universities to help with the war effort by creating ballistics tables for every weapon in the U.S. arsenal. At that time, women in their 20s and 30s were better educated than in previous generations and represented about half the student population at universities, according to the documentary. Once recruited, the women took a short, intensive math course to master the ballistics equations. Then they often toiled away on double or even triple shifts, with no time off for vacations.

Those featured in the film said they were grateful to have the jobs because it gave them the opportunity to leave home and the traditional female roles behind. All said they felt they had a patriotic duty to help win the war. And they were relatively well paid for their efforts. Some earned up to US $1,800 per year, or about $32,000 in today’s dollars.

The women used manual desktop calculators as well as a differential analyzer—an enormous machine that sped up the calculations. It took 40 hours to do one calculation by hand, but only 15 minutes with the differential analyzer. The analyzer wasn't reliable enough on its own, though, so the women often checked the machine’s work by hand. Their calculations were published in booklets that were sent off to the artillery divisions. New ballistic tables were desperately needed; guns often reached the front lines before the tables.

“These women did vital work,” said William F. Atwater, a military historian interviewed in the film. “We could not have won World War II without that data.”

ENIAC was developed to aid the army’s calculation efforts, but it wasn’t operational in time to help with the war effort. To test its capabilities, the women programmed problems for ENIAC to solve. The work was considered largely a clerical job back then, deemed not as important as the engineers who built the machine. But it also was physically grueling. The programmers used 3,000 switches and dozens of cables and digit trays to route the data and program pulses through the machine. And the women taught themselves how to program the computer. Ultimately they could debug the ENIAC down to a vacuum tube, according to the documentary. It wasn’t until 1997 that the six women were inducted into the Women in Technology Hall of Fame.


There are many reasons why the women’s contributions remained unknown for so long. For one thing, their crucial work posed a moral dilemma for many of them. They had to come to terms with the fact that their computations made U.S. weapons more lethal. One woman in the documentary said she never told her children about the type of work she did.

Another reason is that when the war ended in 1945, the women returned to traditional roles of wives and mothers, instead of pursuing careers in technology.

But there also was gender bias. When ENIAC was demonstrated to the public and news media for the first time, for example, the female programmers weren’t invited to the celebration. And when photographs were published of those who worked on ENIAC, they showed just the engineers—all men—even though pictures like the one below of the women existed.

The IEEE Foundation gave a US $10,000 grant to make the documentary, and the IEEE History Center provided assistance with the historical information.

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