DESTINATION MOON: A History of the Lunar Orbiter Program
 
 
CHAPTER II: TOWARD A LIGHTWEIGHT LUNAR ORBITER
 
Early Apollo Impact on Lunar Orbiter Planning
 
 

[11] On June 15, 1962,the Office of Manned Space Flight submitted for the first time since the U.S. manned lunar [12] landing commitment a formal list of requirements to OSS for data on the Moon's surface. The list gave the Office of Lunar and Planetary Programs within OSS its first opportunity to compare the objectives of its lunar programs with preliminary Apollo needs. It re-examined the mission objectives of the Surveyor Lander and acknowledged that Ranger data would not meet the Apollo requirements.

It directed JPL to review all possible ways of converting the Ranger into an orbiter. JPL scientists and engineers soon responded that a conversion was not possible. JPL, in turn, requested the Hughes Aircraft Company, prime contractor for Surveyor, to examine the possibility of designing a 360-kilogram orbiter that the Atlas-Agena rocket could carry on a translunar trajectory. Hughes's report showed that such a lightweight spacecraft would have only a 27-kilogram payload, placing extreme constraints on the visual instrumentation system.6 Following this up, JPL examined the feasibility of using the Agena with a Surveyor Kick Stage which would allow for a spacecraft weight of about 450 kilograms and a payload of 57 kilograms.7 [13] However, this approach would require more research and development. before NASA could pass judgment on its feasibility. Deciding that it did not have time to investigate this approach, the Office of Space Sciences proceeded with the Centaur-class Surveyor Orbiter.

By the end of July 1962 OSS had formulated the basic photographic requirements for the Surveyor Orbiter., but unfortunately these fell below the very demanding needs of Apollo. The Apollo Program required photographic data of the lunar surface that could show slopes of less than 7 with less than 1-meter protuberances and depressions on the surface of the Moon's front side. The first version of the Surveyor Orbiter would be able to shoot stereoscopic photographs of the lunar surface with a resolution only as small as 9 meters and monoscopic photographs which would resolve details as small as I meter. It would cover a minimum area of 100° longitude by 40° latitude from the equator on the visible side of the Moon.8

The spacecraft would most likely employ a television camera system. The Surveyor Orbiter photo system had one great drawback which the Support of Project Apollo document cited: "Landing area coverage of the size required [by Apollo] is not now possible except through repeated Ranger or Surveyor flights into the same area or by means [14] of a photographic roving vehicle or a hovering spacecraft."9

The level of technology in photographic systems for long-life lunar missions had not progressed much beyond the Ranger system, and NASA Headquarters recognition of this fact contrasted markedly with the status of the Surveyor Orbiter, on paper, as of July 20, 1962. Briefly summed up it was:

1. Five flights were planned.
 
2. Centaur rocket was to be launch vehicle; spacecraft weight was to be about 800 kilograms.
 
3. Jet Propulsion Laboratory was to establish design requirements and present them by September 1. 1962.
 
4. Surveyor Orbiter was to incorporate maximum amount of Surveyor Lander hardware and technology.
 
5. JPL was to develop a plan for the evaluation of experiments other than the Visual Instrumentation System by August 17, 1962. NASA Headquarters was to review this.
 
6. No Surveyor Orbiter Project Plan existed. JPL was to develop one and submit it to NASA for review by November 30, 1962.
 
7. A total of $29.5 million in funds existed for the Surveyor Orbiter in FY 1963 and $29.0 million in FY 1964. These funds would be redistributed between Surveyor Orbiter, Surveyor Lander, and the Ranger Improvement Plan only on the basis of defined relative values.10

The Jet Propulsion Laboratory had no operational Surveyor Orbiter program at this time. Indeed the troubles which [15] JPL was experiencing with the Ranger Program acted as a brake on the development of the orbiter.11

 


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