Spacecraft above the Moon.

Artist's concept of Lunar Orbiter at the Moon.

Lunar Orbiter 2's photos covered nearly 1.6 million square miles (4 million square kilometers) of the Moon's surface.

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Lunar Orbiter 2’s mission was to photograph 13 primary and 17 secondary landings sites for the Apollo program in the northern region of the Moon’s near side equatorial area.

After a single mid-course correction on the way to the Moon, on Nov. 10, 1966, the spacecraft entered a 122 x 1,150 mile (196 × 1,850 kilometer) orbit around the Moon. After 33 orbits, Lunar Orbiter 2 was moved to its photographic orbit with a perilune of 31 miles (49.7 kilometers).

On Nov. 18, 1966 it began its photography mission, returning excellent quality medium and high-resolution photographs, including the impact point of Ranger 8. The spacecraft ended its photography mission on Nov. 26, 1966 and transmission of the images was concluded by Dec. 7, 1966, by which time the probe had transmitted back 211 pictures of both the near side and large areas of the far side.

These photos covered nearly 1.6 million square miles (4 million square kilometers) of the lunar surface. The high-gain transmitter failed during this time, but did not significantly affect the coverage afforded by the photos.

On Nov. 23, 1966, Lunar Orbiter 2 took perhaps the most memorable photo of any in the series, a spectacular shot looking across the Copernicus crater from an altitude of only 28 miles (45 kilometers) that vividly emphasized the three-dimensional nature of the lunar surface.

On Dec. 8, 1966, after the main photographic mission was over, Lunar Orbiter 2 fired its main engine to change its orbital plane in order to provide tracking data of the Moon’s gravitational field over a wider swath.

Finally, on Oct. 11, 1967, when attitude control gas was almost depleted, a retro-burn deliberately crashed the spacecraft onto the lunar surface at 4 degrees south latitude and 98 degrees east longitude on the far side to prevent communications interference on future missions.

Source

Siddiqi, Asif A. Beyond Earth: A Chronicle of Deep Space Exploration, 1958-2016. NASA History Program Office, 2018.

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