OAO-B: The components for the Goddard prototype package are now in fabrication. The component tests will take place in the first part of 1964 and the prototype system is scheduled for delivery in latter 1964.

OAO-C: The hardware phase of the Princeton prime ultraviolet experiment has been initiated. Also, in 1963 an X-ray experiment of the University of London was initiated. The prototype experiments for OAO-C will be delivered in 1965.

OAO-D: The experiments for this spacecraft will be selected in 1964.

Future

Following are some future milestones in our investigation of the nature of the universe.

Ultraviolet photographs of Orion from X-15.

Coarse and fine stellar pointing control for Aerobee rockets used to study stars in ultraviolet and X-ray regions.

High resolution photographs of stars and nebulae from Strato-
scope II.

Begin using Beacon EXPLORERS for geodetic studies.
Radio astronomy measurements from EGO.

OAO ultraviolet sky mapping.

Radio Astronomy Satellite.

Objectives

LUNAR AND PLANETARY EXPLORATION

INVESTIGATION OF THE MOON

The primary objectives of the lunar science program are to obtain data on the structure and topography of the lunar surface, the lunar environment, and the physical, chemical, geodetic, and gravitational properties of the Moon. These objectives are translated into project objectives listed in figure 128. The resulting data are of importance to the APOLLO project for the design of manned lunar orbiters, landing craft, and logistic support vehicles, for the calculation of orbits and trajectories of lunar flights, and for the design of operations in the vicinity of and on the Moon. The data will also be important in seeking to understand the origin of the solar system. Progress

The past year was spent in preparation for unmanned flight missions to the Moon as noted in figure 129.

1. A RANGER design validation, quality assurance, and ground test program was instituted.

2. RANGER was readied for an approach TV mission.

3. SURVEYOR system tests in progress.

4. SURVEYOR spacecraft and experiments in final developmental stages.

5. LUNAR ORBITER contractor selected.

6. Additional lunar topographic and geological charts were made. 7. Laboratory and theoretical studies of lunar properties in progress. RANGER status.-The RANGER BLOCK III program (fig. 130) consists of four spacecraft, the first of which has already been launched. Each mission is primarily concerned with obtaining high resolution photographs of the lunar surface as the spacecraft approaches the

SPACECRAFT TESTING UNDERWAY

INSTRUMENTATION UNDER DEVELOPMENT FOR APOLLO SUPPORT
AND SCIENTIFIC STUDIES

FIRST TEST FLIGHT SCHEDULED FOR EARLY 1965

ORBITER

BOEING SELECTED AS SPACECRAFT SYSTEM CONTRACTOR

SPACECRAFT DEVELOPMENT TO BEGIN IN FIRST QUARTER 1964

FIGURE 129

NASA SL64-198

Moon on an impact trajectory. RANGER VI, the first of these four missions, was launched on January 30, 1964, and impacted on the moon on February 2, 1964; unfortunately, however, the television camera failed to operate as planned. RANGERS B, C, and D are in various stages of assembly and checkout at the Jet Propulsion Laboratory and the RCA laboratory in Hightstown, New Jersey.

SURVEYOR status.-The SURVEYOR spacecraft (fig. 131) is being developed to accomplish the first soft landings on the Moon. On the lunar surface, it will survey various landing areas of interest as possible sites for later manned landings and make measurements to improve our understanding of the nature of the Moon. Landed SURVEYORS will transmit to Earth a variety of data, such as highresolution television pictures of the lunar terrain and surface texture, measurements of the surface hardness and other physical and chemical properties, lunar seismic activity, and the meteorite environment near the surface.

The SURVEYOR mission requires the development of a technology far more advanced than that employed in the MARINER II and RANGER spacecraft. Not only must SURVEYOR navigate through the space between the Earth and the Moon, but it must land softly on the Moon, much as a helicopter lands on the Earth but without the benefit of any weight lifting effect of an atmosphere. The complexity of the landing maneuver itself can be best appreciated perhaps by recognizing that the problem is one of backing down a multistage rocket to a landing 240,000 miles and 66 hours removed from the launching site.

Current year funds have been primarily devoted to developmental testing and refinement of components and subsystems, system testing of the proof-test spacecraft, and hovering and drop tests from a balloon which simulate the final landing on the Moon. These dynamic tests have been the means of highlighting areas of design improvements in the various subsystems which contribute to the soft-landing capability of the flight spacecraft. Tether tests conducted by suspending the test spacecraft from a tower have disclosed areas for design improvement in the radar altimeter and Doppler velocity sensor system, in the vernier engines, and in interactions between the two. These design improvements have either been made or are in the process of being made. Finally, our instrument development is progressing nicely. We have in the development stage analysis instruments for both currently scheduled and later additional flights. In many cases, work is beginning on second generation instruments with more versatility and reliability, and requiring less power and weight than the initial models. The final assembly of the first flight spacecraft will be started in the latter part of fiscal year 1964.

Fiscal year 1965 funds will be used for completion of system functional testing, environmental testing (thermal-vacuum, shock and vibration), mission-simulation testing, crew training by mock operations, and tests of dynamic models on CENTAUR development flights. Development of the basic SURVEYOR spacecraft system is expected to be essentially completed and the first test flights started in fiscal year 1965.

A Phase I study has been initiated to determine the feasibility of including a small lunar-surface roving vehicle in the payload of later SURVEYOR spacecraft. It is expected that development of this and other experiments in support of manned landings on the Moon will be continued in fiscal year 1965.

LUNAR ORBITER status.-The LUNAR ORBITER project (fig. 132) was approved August 30, 1963. Proposals were solicited a few days later for the prime contract. Boeing has been selected as the prime contractor, and contract negotiation is underway. The primary goal of the project is the photography of considerable areas of the lunar surface at high resolution for the exploration and selection of landing sites, and for scientific purposes. A secondary objective is

the use of the orbiting spacecraft for other scientific investigations, such as the determination of the shape of the Moon's gravity field from tracking measurements. The first of the five authorized flight missions is planned for the first half of 1966.

Status of Earth-based work for lunar programs.-Telescopic studies of the Moon (fig. 133) continue to play an important part in our Earth-based lunar program. Because the greatest resolution and detail are obtained from visual telescopic studies rather than pictures, telescopes are needed for our detailed lunar mapping and geological work. Recently, a reliable sighting of gas escaping from the area of Aristarchus was obtained at Lowell Observatory. If this phenomenon is a common occurrence, it would not only influence our ideas about the physical and chemical properties of the Moon, but it might also