The original cover design that started it all. Credit: Museum of Science and Industry

It seems slightly unbelievable now, but the scientists who developed the nuclear bomb didn’t want it to be used in an actual war. After the first test bomb exploded in New Mexico in July, 1945, J. Robert Oppenheimer, the head of the Los Alamos lab, said he was reminded of a quote from the Bhagavad Gita: “Now I am become death, the destroyer of worlds.” Later that month, 70 scientists who’d worked on the Manhattan Project, which led to the development of the bomb, signed a petition begging President Truman not to use it against the Japanese.

Well, we all know how that went.

After the war, Oppenheimer and his fellow nuclear scientists felt it was even more important to remind the world of the dangers of atomic warfare. In 1947, a group of Manhattan Project alums called the Chicago Atomic Scientists reconvened at the University of Chicago where they’d spent so much time building the bomb beneath the university football field (now the site of Regenstein Library) and began publishing a newsletter called the Bulletin of the Atomic Scientists. It quickly expanded into a full-fledged academic journal. But its greatest contribution to humanity was the Doomsday Clock, an embodiment of the idea of impending destruction. Midnight represents the end of the world. We’re in the latter half of the eleventh hour. Every year, the scientists meet to decide how many minutes we have left. And now the Museum of Science and Industry has created “Turn Back the Clock,” an exhibit devoted to this extremely creepy artifact of the Cold War.

Credit: Museum of Science and Industry/Luci Creative

However, the first thing you learn from “Turn Back the Clock” is that the Doomsday Clock is not an artifact of the Cold War at all. It is, in fact, alive and ticking and, since 2007, has been taking into account climate change and other forms of environmental destruction. For the first 30 years of its existence, the clock was adjusted by a scientist named Eugene Rabinowitch; now it’s done by a committee that convenes every January. This year, we are at two-and-a-half minutes to midnight, the closest we’ve been since 1953.

When the clock was first set back in 1947, it was at seven minutes to midnight, though the reasons for that were not purely scientific: Martyl Langsdorf, the graphic artist who designed the clock, liked the angle the hands made at 11:53.

The MSI exhibit presents an interactive timeline of the various adjustments to the clock, accompanied by images of various factors that contributed to the decision. In 1984, for instance, the clock was moved to three minutes to midnight due to President Reagan’s escalation of the arms race with the Soviets and the Soviets’ escalation of the war with Afghanistan. But by 1991, the clock was back to 17 minutes to midnight, thanks to the signing of the Strategic Arms Reduction Treaty (START) between the U.S. and USSR. This year’s adjustment, half a minute closer to midnight than the last resetting in 2015, was affected by the tensions in North Korea. The exhibit will be up for about a year, long enough to incorporate next year’s decision.

What do you want to be when you grow up?Credit: Museum of Science and Industry

The exhibit is not entirely gloom and doom, though. There are some select curios from the atomic age, including a comic book called Learn How Dagwood Splits the Atom featuring Dagwood Bumstead, an atomic energy lab kit, and a build-it-yourself model of an atomic power plant. There is also a collection of science fiction books that made predictions just accurate enough to be scary, including The Drowned World, by J.G. Ballard, and a video showing a continuous loop of President Johnson’s 1964 “Daisy Girl” ad, which juxtaposes a little girl counting petals on a daisy with the countdown to detonation of a bomb. (Johnson’s opponent, Barry Goldwater, had advocated for using nuclear weapons to defoliate Vietnam so U.S. soldiers could get a better crack at the Viet Cong.)

There are also displays of letters by scientists, including Albert Einstein, and magazine articles that illustrate the weird combination of fear and optimism that made up the atomic age. Sure, humans now had the power to destroy the world, but if we harness atomic energy properly, look at all the good we could do!

“The larger message,” says Patricia Ward, the museum’s director of science and technology, “is that the clock fosters a sense of agency and greater awareness. We have the capacity to keep ourselves safe. It’s not, ‘We’re all going to die.'”

After all, she points out, even though the atomic bombs of 2017 are 100 times more powerful than the bomb that fell on Hiroshima, there are 14,900 nuclear weapons in the world today, as opposed to 70,300 in 1986. And still, no one has used them since the U.S. bombed Japan in 1945.