December 24, 1968: The First Men to Orbit the Moon

Today is the 38th anniversary of Apollo 8's entrance into lunar orbit, a milestone preceded by extraterrestrial television broadcasts that reached over one billion people. On December 24, 1968, NASA astronauts Frank Borman, Jim Lovell, and William Anders became the first humans to orbit the moon. After a successful launch and trans-lunar injection, the crew of Apollo 8 passed through the Van Allen radiation belts and entered the mission's cruise phase. Approximately 31 hours into the flight, the astronauts provided television viewers with a tour of their spacecraft and attempted to show images of Earth. Unfortunately, the lenses for Apollo 8's black-and-white camera lacked suitable filters, causing the blue and white planet to appear as a bright blob. To close Apollo 8's first television broadcast, Jim Lovell wished his mother a happy birthday before the spacecraft and its high-gain antenna passed out of view of receiving stations back on Earth.

The crew of Apollo 8 provided viewers with a second television broadcast at 55 hours into the flight. Although the camera filters they had crafted were better-suited for a still camera, the astronauts managed to use a telephoto lens to capture discernible images of Earth. Soon after the 23-minute transmission ended, Apollo 8 entered the lunar sphere of influence and began preparations for Lunar Orbit Insertion-1 (LOI-1). At nearly 69 hours into the flight, the spacecraft went behind the moon and out of radio contact with mission control. For four long minutes, the service propulsion system (SPS) engine burned, finally placing the crew of Apollo 8 in a 193.3 mi (311.1 km) by 69.5 mi (111.9 km) orbit around the moon. If the burn had lasted too long, the spacecraft could have crashed upon the surface of the moon. If the burn had ended too soon, Apollo 8 could have entered a highly elliptical orbit, or been flung off into space.

After emerging on the sunlight side of the moon, the astronauts began their scheduled reconnaissance activities, photographing the lunar surface and identifying potential sites for future landings. Ultimately, the crew would take over 700 photographs of the moon and over 150 pictures of the Earth. As Apollo 8 rounded the moon for the ninth time, each astronaut took turns reading from the Book of Genesis and wishing the world a Merry Christmas. The moon, Mission Commander Frank Borman observed, is "a vast, lonely, forbidding type of existence or expanse of nothing".