Before Apollo missions landed on the Moon, NASA launched a series of orbiters to photographically explore the lunar surface to identify possible landing sites.
On February 4, 1967*, engineers from the Lewis Research Center (now Glenn) directed the launch of Lunar Orbiter 3. The nearly nine-month mission provided NASA planners with the imagery and data necessary to decide on the final landing sites.
A 25-person Lewis team traveled to Pad 13 at Cape Kennedy (now Cape Canaveral) in late January of that year to carry out the Lunar Orbiter 3 launch. The team had managed 18 prior launches of the Atlas-Agena launch system by defining the launch vehicle requirements and overseeing the design, fabrication, testing and integration of hardware.
At 8:17 p.m. ET, the Atlas-Agena lifted off the pad into the clear night sky and just over five minutes later, the Agena separated from the Atlas and fired its 16,000-pound thrust engine to enter a parking orbit for approximately 10 minutes.
It was critical that the spacecraft commenced its lunar trajectory at a very precise location 118 miles from Earth. The Lewis team timed the reignition of Agena’s engine nearly perfectly. Lunar Orbiter 3 entered its translunar injection point within 7.5 mph of the intended 24,450 mph velocity. This resulted in a mid-course correction of a mere 3.3 meters per second as the spacecraft sailed toward the Moon.
The first two Lunar Orbiters photographically explored the surface of the Moon to identify possible landing sites for Apollo. Lunar Orbiter 3 successfully provided additional information on the 12 most promising sites and gathered scientific information from 32 additional locations. Lewis subsequently launched the final two Lunar Orbiters, which provided additional scientific data.
*Official NASA sites list the launch date as Feb. 5 when using Greenwich Mean Time (GMT).
Robert S. Arrighi
NASA’s Glenn Research Center
