Apollo 8: Astronavigation and Guidance Systems

2. The Crew of Apollo 8 James Lovell navigated to the Moon and back. In 1968 he was the command module pilot on Apollo 8. In 1970 he was the commander of Apollo 13, the aborted lunar landing mission. Although assisted by his crew, he had the primary responsibility of getting the spacecraft to the Moon and back.

3. Astronavigator An astronavigator uses an arrangement of a globe and star charts. Soviet cosmonauts used this one to supplement their ground-based navigation system by adjusting the constellations on the globe to match the stars they could see.

4. Engineer’s Sketch This sketch shows how an astronavigator might operate. It shows how the images of a star field and globe were superimposed over what the astronaut observed through the capsule’s window.

5. Sighting a Star in Space Jim Lovell using the sextant and telescope on board Apollo 8. After he identified a star, he would enter that information into the Apollo Guidance Computer.

6. Apollo Star Chart Apollo astronauts used star charts that showed the locations, names, and code numbers for a select group of stars. The astronauts would key those numbers into their Apollo Guidance Computer while taking readings with a sextant.

7. Apollo Guidance, Navigation, and Control System Just like at sea, celestial navigation involved taking readings with a sextant. In space these readings were automatically fed in to the Apollo Guidance Computer—the electronic equivalent of the almanacs and mathematical tables sailors use.

8. Apollo Guidance Computer This Apollo crew used sightings on stars, the Moon, and Earth to update navigational data store in the Apollo Guidance Computer, which calculated the spacecraft’s velocity and location. The results were compared with data computed by Earth-based tracking stations.