December 21, 1968—Four days before Christmas

THREE ASTRONAUTS ARE STRAPPED INTO A small spacecraft thirty-six stories in the air, awaiting the final moments of countdown. They sit atop the most powerful machine ever built.

The Saturn V rocket is a jewel of the National Aeronautics and Space Administration, a vehicle that will generate the energy of a small atomic bomb. But it has never flown with men aboard, and it has had just two tests, the most recent of which failed catastrophically just eight months earlier. The three astronauts are going not merely into Earth orbit, or even beyond the world altitude record of 853 miles. They intend to go a quarter of a million miles away, to a place no man has ever gone. They intend to go to the Moon.

Beneath them, the United States is fracturing. The year 1968 has seen killing, war, protest, and political unrest unlike any in the country’s history, from the assassinations of Martin Luther King, Jr., and Robert Kennedy to the unraveling of Vietnam to the riots in Chicago. Already, Time magazine has named THE DISSENTER its Man of the Year.

As the countdown begins, there are engineers and scientists at NASA who question whether the crew will ever return. Even the astronauts are realistic about their chances of surviving the flight, an operation riskier than anything the American space agency has ever attempted. One of them has recorded a final goodbye to his wife, to be played in the event he doesn’t return.

In August, this mission did not exist. Nearly everything that has gone into its planning—the training, analysis, calculations, even the politics—has been rushed to the launchpad in a fraction of the time ordinarily required. If anything goes wrong, public opinion—and the will of the United States government—might turn against NASA. The fate of the entire space program hangs on the crew’s safe return.

As the moment of launch draws near, one of the astronauts spots a mud dauber wasp building a nest on the outside of one of the spacecraft’s tiny windows. Back and forth the insect moves, grabbing mud and adding to its new home. The astronaut thinks, “You are in for a surprise.”

Vapors begin to spew from around the base of the giant rocket. Less than a minute remains before lift-off. When the five first-stage engines ignite, they will deliver a combined 160 million horsepower. In the final few seconds, a typhoon of flames unfurls to either side. Beneath the astronauts, it is not just the launchpad that begins to shake, but the entire world.