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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 F 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

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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/r-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 atmos

pheric 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 disci

plines. 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, ocear

eanography, agriculture,

geodesy and geology.

Progress in understanding of the earth's space environ

ment 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

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.'

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Indicative of the intensive study and painstaking plan

ning 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

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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 -- 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 sci

entific 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

tent, 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 observa

tories 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 understand

ing 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 Hornig, 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.

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Why is there so much interest in this particular telescope?

Many astronomers believe, and there are observations to suggest,

that the universe started some 10-20 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

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