12 Oct 2008 LOIRP Status Earth/Moon Picture Decision

Destination Moon: A History of the Lunar Orbiter Program, NASA TM X-3487
Of all the pictures which Lunar Orbiter I made, one of the most spectacular was the first photograph of the Earth taken from the vicinity of the Moon. This picture was not included in the original mission plan, and it required that the spacecraft’s attitude in relation to the lunar surface be changed so that the camera’s lenses were pointing away from the Moon. Such maneuvering meant a calculated risk and, coming early in the flight, the unplanned photograph of Earth raised some doubts among Boeing management about the safety of the spacecraft.
Robert J. Helberg, Boeing’s Program Manager for Lunar Orbiter, opposed such a hazardous unnecessary risk. The spacecraft would be pointed away from the Moon so that [242] the camera’s lenses could catch a quick view of Earth tangential to the lunar surface. Then, once the pictures were made (flight controllers would execute two photo sequences on two different orbits), Lunar Orbiter I would disappear behind the Moon where it would not be in communication with ground control. If, for some reason ground control failed to reestablish communications with it, the Apollo-oriented mission photography would probably remain undone, Moreover, Boeing had an incentive riding on the performance of the spacecraft, and Heiberg did not think it prudent to commit the spacecraft to a series of maneuvers for which no plans had been made. 30
The understandably conservative Boeing stance was changed through a series of meetings between top NASA program officials, including Dr. Floyd L. Thompson, Clifford H. Nelson, and Lee R. Scherer. They convinced Heiberg that the picture was worth the risk and that NASA would make compensation in the event of an unexpected mishap with the spacecraft. After agreement had been reached, Lunar Orbiter flight controllers executed the necessary maneuvers to point the spacecraft’s camera away from the lunar surface, and on two different orbits (16 and 26) it recorded two unprecedented, very useful photographs.
[243] The Earth-Moon pictures proved valuable for their oblique perspective of the lunar surface. Until these two photographs, all pictures had been taken along axes perpendicular or nearly perpendicular to the Moon’s surface. On subsequent Lunar Orbiter missions oblique photography was planned and used more often. 31
30. Taback interview. See also Transcript of Proceedings–Discussion between Nicks, et al., and members of National Academy of Public Administration, pp. 111-112.
31. For a detailed technical description of the Earth-Moon photographs refer to Lunar Orbiter I Photography, NASA CR-847, prepared by Boeing Company, Seattle, Washington, for the Langley Research Center, August 1967, pp. 64-71.

The Orbital Period for LO-1 was 3 hrs 26 minutes and 21 seconds – that’s 34.3 hours between orbit 16 and 26 …. you could have had orbit 16 on 23 Aug and orbit 26 on 25 Aug …

1. If you listen to this audio [ http://images.spaceref.com/news/2008/loirptest5.mp3] from a data tape you will hear the technician state that it is an analog copy of an earlier tape – but that it is only a copy of the portion with the Earth and moon on it and that it was originally recorded on GMT date 237.
2. In 1966 day 237 was 25 August. Lunar Orbiter 1 was launched on 10 August 1966 and imaged the moon from 18-29 August 1966.
So, NASA NSSDC says that this image was taken on 23 August yet the tech’s voice says day 237 – this must be the date when the tape was being played back from the spacecraft to Earth, yes

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