in research projects utilizing balloons and aircraft. Nearly 400 research tasks are being conducted at universities, nonprofit and industrial research centers, NASA Centers, and other Government agencies.

Concluding Remarks

In summary, the objectives of the Physics and Astronomy Programs are to advance our knowledge and understanding of the space environment and the universe. These Programs have provided us with a new and detailed view of the environment of the Earth in space. They have given us a glimpse of the exciting new solar and stellar phenomena through the windows not open to us from the Earth's surface.

The emphasis in space physics is shifting from the initial exploration and mapping of the environment to the phase of understanding the mechanisms which control the environment.

Space astronomy is beginning to have available the complex automated observatories necessary to proceed beyond the initial exploratory phase. During the early 1970's both automated and manned systems will be used to conduct astronomical observations in space. These missions will determine the proper roles for man and automation in the long-range thrust of space astronomythe establishment of permanent observatories in space.

LUNAR AND PLANETARY EXPLORATION

The goals of the Lunar and Planetary Exploration Programs are to systematically study and understand the solar system and to apply that knowledge to assist in the solution of problems that mankind faces on Earth. Specifically, we are striving to understand the origin and evolution of the solar system, the origin and evolution of life in the solar system; and, most importantly, the dynamic forces that shape man's environment on Earth.

Why should we explore the solar system? Aren't there still things to be learned

about the Earth? Couldn't we use our energies and our resources to better advantage on Earth to help solve some of our more immediate problems?

The first and perhaps the most important reason for exploring the solar system is the satisfaction of the fundamental drives which man has to explore his environment and to understand and master that environment. Society must be able to provide an outlet for those drives if it is to remain a healthy society. The voyage of Apollo 8 to the Moon, with its view of the Earth as a beautiful but lonely oasis in the vastness of space, helped for a moment to unite a torn and troubled world. The Apollo 8 mission helped to restore man's confidence in his ability to do great and miraculous things. It gave man a different view of the Earth and helped him realize how precious the "good Earth" is, helped him realize how small and lonely is the world he knows and how vast is the ocean of space that surrounds it.

Another important reason for exploring the solar system is the knowledge and understanding that it will bring to a solution of some of the problems of preserving and protecting our world. We know that man, through industrial revolution and an increasing population, is not only polluting the atmosphere, but may be changing its very nature. We have testified in previous years that the amount of carbon dioxide in the atmosphere has changed by a significant amount in the past 50 years. We also know that there have been major climatic changes in the past, but we do not understand the reasons for those changes. Our knowledge of the processes at work is so minimal that we are not sure whether the atmosphere is slowly warming due to increasing amounts of carbon dioxide or slowly cooling because of the impurities in the air reflecting the sunlight away from the surface of the Earth. With our present knowledge we cannot even be sure whether the surface of the Earth would become cooler or warmer if the temperature of the Sun increased a few degrees. Our meteorological satellites and atmospheric Explorers are giving us invaluable insight into our atmosphere, but with them we can only study that atmosphere as it is today, not as it was or as it may become. Nor can we conduct large-scale experiments to attempt to get a better insight into the processes which determine our environment. However, in a detailed investigation of our sister planets, Mars and Venus, we can study the properties of the atmospheres of similar planets which are not at the same distances from the Sun as the Earth and perhaps are at different stages in their evolution, and with quite different kinds of atmospheres. A comparison of the properties of these atmospheres and an understanding of why they are different will give atmospheric physicists a new body of knowledge and a new perspective from which to tackle the problems we face on Earth.

Of no lesser importance is the knowledge to be gained by studying the interior of the other bodies of the solar system. Recently, the theory of continental drift on the Earth has received considerable support and has provided one theory on the origin of earthquakes. The discovery of similar drifting continents on other bodies could substantiate this theory and lead to further understanding of the cause of Earth's destructive earthquakes.

In exploring the solar system over the past decade, we have been following a systematic strategy which we believe is sound and should be followed through the next decade. This is a strategy in which we make preliminary or exploratory studies of several planets while at the same time concentrating on a particular object or planet for detailed studies. In the early years of the space program, we began the detailed study of the Earth and its environment which I just described while we conducted exploratory studies of the Moon with the Ranger, and of Mars and Venus with the early Mariner missions. Systematic detailed studies of the Moon have been made with Lunar Orbiters and Surveyors beginning in 1966 and ending with Surveyor VII in January 1968.

With the completion of the detailed studies of the Moon with automated spacecraft, we are taking those teams of people and those systems and techniques and initiating the detailed study of the planet Mars. We are planning four orbital missions-two in 1971 and two, working with the first soft landers on the Martian surface, at the 1973 Mars opportunity (Chart SL69-288).

At the same time that we are beginning the detailed study of Mars, we will expand the preliminary exploration of other planets, in toward the Sun to Mercury and out to Jupiter. In 1972 and 1973, Pioneers F and G will be sent to the vicinity of Jupiter.

As we look beyond the early 1970's the planetary exploration attention begins to focus on a series of unique opportunities in the late 1970's, which we call

CHART 288

the Grand Tour Mission, when it will be possible to use a single spacecraft to explore Jupiter, Saturn, Uranus, and Neptune. In addition to these unique opportunities to visit four planets with a single spacecraft, there are also several opportunities in the late 1970's to visit two or even three of the outer planets during a single mission. We could send a spacecraft first to Jupiter and then, by using the gravitational field and the orbital velocity of Jupiter, the spacecraft would proceed on to Saturn, Uranus, Neptune, or Pluto. While we are sending exploratory spacecraft to the outer planets in the late 1970's, our strategy calls for continued emphasis on the detailed studies of Mars with larger landers, and perhaps a sample return mission, all with automated spacecraft. We would also expect to be starting more detailed studies of another planet, perhaps Venus and Jupiter.

I shall now discuss the achievements in the lunar science and the planetary exploration programs, the activities planned for 1969, and the program proposed for Fiscal Year 1970.

Lunar science

While the pre-Apollo automated phase of lunar exploration has been completed, the flight of Apollo 8 opened the next phase in the study of the Moon when man himself will begin to explore the Moon, make detailed observations, return samples, and perform other experiments. The Office of Space Science and Applications remains responsible for establishing the scientific objectives; maintaining the scientific establishment required for lunar exploration; working with the Office of Manned Space Flight and other elements of the Agency to plan the flight programs; and selecting the scientific investigations to be conducted to accomplish our objectives.

The outstanding success of Apollo 8, the likelihood of a successful manned lunar landing in 1969, and the capability of the Apollo system to land heavy payloads on the lunar surface all emphasize the need for planning the next phase of lunar exploration. To support the scientific objectives of Apollo, and to continue the analysis and interpretation of Surveyor and Lunar Orbiter data, we are requesting $11.5 million for Lunar Science in the Lunar and

26-868 0-69-pt. 3-3

Planetary Supporting Research and Technology effort. The $11 million for Lunar Exploration in the Office of Manned Space Flight budget is for flight systems design studies. There are plans to conduct design studies of modifications to the Apollo hardware to obtain longer staytimes on the lunar surface, systems to aid manned mobility, and supporting automated systems. Neither the planning of scientific objectives by the Office of Space Science and Applications nor the design studies by the Office of Manned Space Flight commit the Agency to a post-Apollo lunar exploration program. However, such efforts are necessary to hold the post-Apollo option open for later consideration after the manned lunar landing.

Apollo 8 was the most noteworthy achievement in manned lunar exploration in 1968. Charts S69-476, 477, and 514 show some of the spectacular photographs taken by the Apollo 8 astronauts. While Apollo 8 was the outstanding achievement in the area of lunar exploration, we should not forget that on the 10th of January 1968 we successfully soft-landed Surveyor VII in the rough highlands north of the Crater Tycho. Chemical analyses performed by Surveyor VII on three separate lunar samples-the undisturbed surface, a small rock, and an area scraped by the surface-sampler-showed that the lunar material in this region contained significantly less of the heavier elements than had been found by Surveyors V and VI in two widely separated mare regions. This chemical difference may explain the brighter appearance of the highlands compared to the maria and also suggests that, perhaps, the material is of slightly lower density.

A very level uniform area is necessary for the first manned lunar landing to ensure mission success. However, the data from the early Surveyors and Lunar Orbiters show that those regions are not the most interesting regions to explore on the Moon. They are not the areas where man could visit many of the boundaries between different geological formations or study the highlands, as was done with Surveyor VII. Later missions to the Moon will go to sites selected on the basis of their scientific interest and potential for scientific discovery, and their suitability to provide a better understanding of the processes which have taken place on the Moon.