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Dr. HANDLER. I would like to have with me my associate Mr. Milton Rosen, who is Executive Secretary of our Space Sciences Board; and Mr. Clotaire Wood, who serves similarly with our Space Applications Board.

Mr. FUQUA. They will be most welcome to join.

Dr. HANDLER. Mr. Chairman, your hearings are most timely. At the Academy on Tuesday, January 31, we shall commemorate the historic day when the United States entered the Space age. Twenty years ago, on that date, at a press conference close to midnight, at the Academy, representatives of our U.S. National Committee for the International Geophysical Year (IGY), of the Jet Propulsion Laboratory and of the Redstone Arsenal announced the first successful launch of a U.S. spacecraft, Explorer I, into Earth orbit as part of this country's contribution to IGY. That press conference was transformed into an instant celebration. I hope that each of you will be able to join us in this anniversary celebration at the Academy or at the symposium on space science on the following day.

Explorer I climaxed a jittery entry of U.S. science into space, but those shaky beginnings have borne spectacular scientific fruit.

These hearings will provide an opportunity for reemphasizing the conclusions reached in your committee's hearings in 1975, 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. Those initiatives have taken place under the auspices of the Space Science Board of our Assembly of Mathematical and Physical Sciences and the Space Application 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 million, about 18 percent, for the space sciences program. That is my calculation taken from the "big book" and I cannot reconcile it with the special analysis section of the budget which indicates the increase to be even larger.

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.

In essence, what we have learned about the universe has been made possible by the new found ability to utilize those aspects of the electromagnetic spectrum which are not available to us here on Earth.

So we have witnessed extraordinary access to the heavens by X-ray astronomy, ultraviolet astronomy, and gamma ray astronomy. Radio astronomy can be done here on Earth. And it has been, of course, a superlative adjunct to the whole enterprise. Collectively these techniques have given us a completely new view of the universe in which Earth passes.

There is one area of the spectrum which has not yet been fully utilized, and that is the far infrared. That opportunity is now shortly in the offing, and I look forward to that date, when I am sure more surprises will be in store. Taken all in all, this has been an absolutely remarkable episode of man's understanding of where we are.

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 included resource mapping and ecology, oceanography, agriculture, geodesy, and geology.

Progress in understanding of the Earth's immediate 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-for example, in synchronous orbitare limited by diverse radiation 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. Knowledge of 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

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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 exclusivly on the grounds of its practical payoff, that payoff has been handsome indeed.

It is possible, however, only as a consequence of long term, systematic, careful planning.

We have several superb examples of how that has been done. Among them, 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 must be adequate, careful 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 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, at its first conclusion, said:

The Large Space Telescope would make a dominant contribution to our knowledge of cosmology-to our understanding of the content, structure, scale and evolution of the universe.

Reports issued by the Board in 1974 and 1975 recommended a start of the Space Telescope project by NASA. The 1975 report said specifically, "It is clear that the time is now ripe for a start on this important project; nothing is to be gained by delay." In 1976, the Board assembled a group of 20 astronomers from North America and Europe to discuss astronomical observatories in space. The brief report of this group contained a chapter on science with the Large Space Telescope, a chapter which described the contribution it could make to understanding of cosmology, to the distance scale of the universe and to the evolution and morphology of galaxies.

Last year, in view of the promising prospect of congressional approval for the space telescope, NASA asked the Board to recommend appropriate institutional arrangements for optimal use of the telescope, once it is in orbit. A special study group, led by Donald Horning, recommended that NASA form an Institute to be operated by a consortium of universities in order to provide the long-term guidance and support for the scientific effort, to provide a mechanism for engaging astronomers throughout the world, and to provide a means for dissemination and use of data derived from the space. telescope.

We have every reason to believe that the space agency will utilize that advice when the time comes.

But why is there so much interest in this particular telescope? Many astronomers believe, and there are observations to suggest, that the universe started some 10 to 20 billion years ago with a cosmic explosion, often referred to as the "Big Bang," in which all the matter of the universe was created and then started to expand. This expansion

continues today, albeit seemingly at a decreasing rate. The questions that fascinate present-day cosmologists include: How fast is the expansion decelerating? Is this decrease uniform in space and time? What will be the fate of the universe-expansion forever or an eventual collapse into a "primordial fireball," followed by rebirth and eternal recycling?

Although the space telescope may not provide definitive answers to these great questions, it can and will gather more understanding of them than we have ever known before. It can look 10 times as far into space as the most powerful ground-based telescopes, and it has 10 times the resolution; that is, it can discriminate between objects one-tenth as far apart. Thus, we may be able, for the first time, to see and study individual stars in distant galaxies. In addition to this immense scientific return, the task of fabrication of this telescope, placing it in orbit, and rendering it operational is a fit challenge to the developing capability of man to engage in those applications of space technology that will be possible only when the Space Shuttle has become a functional reality.

A second example of long-term planning for space science deals with a NASA project that has been in the public eye for the past year, the landing of the Viking spacecraft on the surface of Mars. Planning for Viking began a decade earlier, and our Board was continuously involved. The purpose of these landers was to make physical, chemical, and biological measurements of the Martian surface and atmosphere; the studies of the physical nature of Mars were extraordinarily successful, but perhaps greatest attention attached to three experiments intended to ascertain whether "life" exists on Mars. A recently released Space Science Board report evaluated the data from these experiments, and recommended a future course for biological investigations of Mars. The report says:

Viking has neither confirmed nor ruled out current or past Martian life. Organic compounds have not been detected. Although all three biology experiments have yielded signals that indicate chemical activity, the interpretation of the signals remains ambiguous or inconclusive. Abiogenic explanations seem likely for at least two of the experiments and probably for a third. We believe that it is preferable to predicate future strategy on the assumption that the signals are not biological in origin.

In other words, life may or may not exist on Mars-but if so, Viking did not find it. The report goes on to say that if life does exist, it will be difficult to find; the report suggests looking in more favorable places; that is, underneath the surface and at edges of the polar icecaps. Importantly, the report recommends that the "long-term objectives of exobiology and surface chemistry are best served by the return of a unsterilized sample to Earth."

What is the significance of all of this to us here on Earth? Again I quote from the Board's report:

It is customary to think that life exists only on planets that provide the proper conditions for its maintenance. But the realization is growing that life itself may modify a planet's surface and atmosphere to optimize conditions for its existence. Even if it were demonstrated that life does not now exist on Mars, the question would remain whether Earth and Mars differed sufficiently in their early histories to permit the origin of life on the former but not the latter. Or alternatively, did both planets permit the origin of life and then diverge dramatical

ly? If so, did the type and extent of life that eevolved play a major role in that divergence?

These questions are of fundamental scientific interest, and they may also be questions of fundamental importance to all of us on Earth. We have clearly reached the point where human activities are exerting global effects on the composition of the Earth's surface, atmosphere, and perhaps its temperature. Atmospheric pollutants may affect the ozone layer and could modify the Earth's albedo.

The burning of fossil fuels has already measurably increased the carbon dioxide content of the atmosphere, and some scenarios contemplated by our Geophysics Research Board predict serious, even devastating consequences if major fractions of our energy requirements continue to be derived from these sources, a process that would be markedly accelerated by large-scale transition form hydrocarbons to coal as our principal energy source.

Clearly the stability of equilibria and steady-state processes on the Earth's surface and in its atmosphere to human perturbants, and the role of the Earth's biota in this stability, are matters of more than arcane interest. Since the surface of Mars provides a natural global system for comparison with Earth, it seems likely that studies of biology, if any, and of chemical evolution on our neighboring planet will shed important light on these terrestrial questionsquestions that could be significant to our ultimate survival.

Let me turn to a third example of scientific inquiry in which the significance of long-term planning becomes obvious-climate. We are embarked on a comprehensive effort to understand both the shortrange phenomena of weather and the long-term processes more properly called climate. Observations of Earth from space have already demonstrated their power as a new and powerful tool for observing, measuring, and cataloging conditions that influence climate on this planet. But what measurements should be made? How often? To what precisions, and for how long? These questions will be addressed in the proposed NASA climate program, a program that was formulated with assistance from the National Research Council. In 1976, at the request of NASA, a coordinating committee for the NASA climate program was appointed; this committee drew upon all of the resources of the NRC; namely, more than a dozen separate committees that have been studying climate dynamics for the past decade.

One of the principal contributions of this committee was a new way of looking at climate, not as one large hopelessly complex problem, as it had sometimes been viewed before, but by dividing it up into four distinct categories of problem areas, each of which permits development of an appropriate subprogram for observation.

The first category attempts to discern what is going on right nowwhat is the water content of the soil? How much snow is stored in the mountains? What is the temperature of the oceans throughout the world? The second involves the prediction of weather in individual regions of the globe on a time scale ranging from a month to a decade. This category offers the promise of progress in the near future, and the initial impetus of NASA's climate program will be in this area; that is, on the understanding of the seasonal and interannual climatic variations. The third category involves study of the reasons for the change of global climate over periods longer than a decade. Historically, significant global changes have occurred over periods as short as a few decades. But not much less than that.

The final category involves an attempt to assess the significance of human activities on both regional and global climate. This goal is dis

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