It hadn't been a very good year.

Nineteen-sixty-eight saw the Tet offensive in Vietnam, the assassinations of Martin Luther King Jr. and Robert F. Kennedy, the Soviet invasion of Czechoslovakia, riots across the world and the My Lai massacre.

But on Christmas Eve, Americans turned on their TVs to see perhaps the first good news all year: Apollo 8 astronauts reading from the Book of Genesis as they became the first humans to orbit the moon.

"And God said, Let there be light: and there was light," read Lunar Module Pilot William Anders.

His crewmates, Commander Frank Borman and Command Module Pilot Jim Lovell, followed with more verses.

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The Apollo 8 crew wasn't even supposed to have gone to the moon. The mission was planned as a low-Earth orbit to test the Lunar Module, the lander later used by Apollo 11 and subsequent missions to land on the moon's surface.

But production delays meant the Lunar Module wouldn't be ready for testing until February 1969. Since the orbiter, the Command Module, had already been thoroughly tested, a decision was made in August 1968 to send Apollo 8 into lunar orbit instead.

That gave the crew only four months to rush through whole new round of training. It's estimated they spent seven hours training for each actual hour of the mission. The night before the launch, they were visited by hero aviator Charles Lindbergh and his wife, as Lindbergh recounted his famous 1927 solo transatlantic flight.

The Saturn V rocket launched on Dec. 21 without major incident. One the way to the moon, Borman got sick, which sent globules of bodily fluids floating around the cabin — the first documented case of space sickness.

Nearly three days after launch, the braking engines fired and the Apollo 8 capsule went into orbit around the moon. The astronauts gazed down upon the lunar craters, the first humans to see them from so close.

"The Moon is essentially gray, no color; looks like plaster of Paris or sort of a grayish beach sand," Lovell reported back to Mission Control.

The astronauts orbited around the moon a total of 10 times over 20 hours, reading from Genesis during the ninth orbit. The journey back to Earth, which began on Christmas Day, was uneventful, though hardly calm; the astronauts themselves had given their mission only a 50-50 chance of succeeding.

But when they got back to Earth, they were hailed as conquering heroes. Time magazine named the trio Men of the Year. Life magazine called their famous color photograph of the Earth rising over the moon one of the "100 photos that changed the world."

Notable atheist Madalyn Murray O'Hair sued NASA over the Genesis reading, but the court ruled it had no jurisdiction over events in space. And Borman got an anonymous telegram that said simply: "Thank you Apollo 8. You saved 1968."

Forty Christmas Eves later, it's best to remember the line that Borman closed the Genesis reading with: "Good night, good luck, a Merry Christmas — and God bless all of you, all of you on the good Earth."