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combining the intangible motiviation of human adventure with

an extraordinarily careful mode of systematic, long-term

planning.

These hearings provide an opportunity for reemphasizing the conclusions, reached in your committee's hearings in 1975 on Future Space Programs, concerning the need to give adequate consideration to the widest possible range of longer term opportunities if we are to assure that the scientific and technological bases will be developed in time to support them. Only recently, the chairman of our Space Science Board pointed out to me that one of the greatest difficulties in optimizing the conduct of new space science initiatives is gathering sufficiently early acceptance and commitment to such initiatives as to assure adequate long-term planning.

Now, let me outline for you some of the activities within the National Research Council, since those 1975 hearings, that concern future scientific opportunities in the space program and the application of space technology to other societal needs. These initiatives have taken place under the auspices of the Space Science Board of our Assembly of Mathematical and Physical Sciences and the Space Applications Board of our Assembly of Engineering; their combined efforts represent the National Research Council's contribution to a continuing, evolving strategy for developing priorities in space science and technology. My subsequent remarks are all informed by the deliberations of those two Boards.

First among the objectives set forth in the Space Act

of 1958 is, "The expansion of human knowledge of phenomena in the atmosphere and space." In pursuance of this objective NASA devotes a major share of its resources to space science. I am pleased to note that the Budget Request just submitted by the President includes an increase of $79 millions, about 18%, for the Space Sciences program

In the early

history of the program, the scientific community at large was somewhat skeptical of the Space Sciences program, unsure of its intellectual merit and concerned that it might become a large-scale diversion from the always limited total resources that government can make available for support of science. That concern has abated, perhaps even vanished. The entire scientific community applauds the remarkable accomplishments of two decades and enthusiastically supports this extraordinarily productive component of the nation's science endeavor. Today there is more good science to be done in space than NASA can afford to do.

The primary accomplishment of space science has been research in areas which simply could not be effectively explored before the possibility of space experimentation. Let me note a few instances

instances(3

Until only yesterday, man's appreciation of the

heavens was limited to what could be seen, i.e., learned

from incoming radiation in that part of the electromagnetic spectrum to which our eyes are sensitive.

The advent of

radio astronomy, performed on the ground brought with it a

colossal new appreciation of previously unimagined celestial phenomena. It is safe to state that the impact of spacebased X-ray astronomy, funded essentially entirely by NASA has been as great as that of radio astronomy and has, to a significant extent, "revolutionized" astronomy. (However, one should recall that the initial discovery of the first nonsolar X-ray source was made with Air Force funding and that solar X-rays were first discovered using Navy funding.) One may now expect that access to any large region of the electromagnetic spectrum, previously unexplored because of the earth's atmospheric attenuation, would have a significant impact on astronomy. Research in the ultraviolet/ X-ray/y-ray spectral region has proved extraordinarily dramatic. Hence, when far infrared astronomy, which is just now developing, begins seriously to use the available space-based observatories, yet additional astronomical breakthroughs should be anticipated.

Clearly the immense recent contributions to lunar and planetary exploration are virtually entirely accounted for by space science.

Study of the earth's upper atmosphere depends almost solely on spacecraft utilization for instrument platforms. The study of other planetary atmospheres and their evolution is also critically dependent upon space probes. The properties of the ionosphere permit a greater amount of information regarding it to be determined from the ground, but, even so, perhaps two-thirds of what is now known about

ionospheric processes derives from the space component of that science. Nearly all that is known regarding atmospheric interactions with the magnetosphere depends on the space segment of such studies.

The view of Earth provided by Landsat and various meteorological satellites is invaluable for several disciplines. Perhaps half of current knowledge regarding the earth's surface and its changes was acquired by surveys conducted from spacecraft. The sciences affected include resource mapping and ecology, oceanography, agriculture, geodesy and geology.

Progress in understanding of the earth's space environment and of the effects of this hostile environment on materials is a unique product of space science. We have learned that the lifetimes of spacecraft at high altitude e.g., in synchronous orbit are limited by diverse radia

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tion effects that may also affect their sensors; spacecraft in low altitude orbits are subjected to atmospheric drag which may cause errors in reporting their positions and thus limit their lifetimes. These understandings have proved invaluable in planning systems for both military and civilian use. Radiation belt physics and the physics and chemistry of the atmosphere have become essential ingredients in the design of all space systems. And, of course, all downlooking, earth observing systems must contend with the radiation from the earth's atmosphere in the various wave length intervals of

interest, knowledge now vital to military and Landsat applications. Finally, knowledge of the consequences of solar absorption at the various levels of the earth's envelope, and the dynamics of mixing of chemicals, and movement of electrical and magnetic fields is becoming critical to weather prediction. Thus, while I would be loath to justify fundamental research exclusively on the grounds of its practical payoff, that payoff has been handsome indeed.'

Indicative of the intensive study and painstaking planning that has gone into the formulation of strategies for space science endeavors are such examples as the space telescope, the Viking landings on Mars, the Jupiter Orbiter Probe, the High Energy Astronomy Observatory, and the proposed NASA climate program. Before commitment to these programs, there салекие

must be adequate scientific justification; thereafter it is imperative that they be planned in utmost detail.

The task of our Space Science Board is to advise NASA in making choices among competing alternatives, all of which are attractive and important

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to seek and to define excellence

in space science and then to assist in the subsequent planning. For over a decade that Board has studied the potential scientific uses of a large optical telescope in space. In 1969, an ad hoc committee of the Board, chaired by Lyman Spitzer, issued a report which, as its first conclusion, said "The Large Space Telescope would make a dominant contribution to our knowledge of cosmology to our understanding of the con

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tent, structure, scale, and evolution of the universe."

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