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NATIONAL AERONAUTICS AND SPACE ACT
Senator ANDERSON. Yes.
Mr. SILVERSTEIN. This specific impulse, with the rockets we now have, is around 245 at sea level; that would do it.
Senator ANDERSON. What would nuclear propulsion be a specific impulse there would start at close to a thousand?
Mr. SILVERSTEIN. Nuclear propulsion could start at about 800. Senator ANDERSON. That's close to a thousand. Mr. SILVERSTEIN. In outer space, that might go to a thousand. Senator ANDERSON. So, it is 4 or 5 times what the devices now have. Would that not simplify the problem a little?
Mr. SILVERSTEIN. In the long-term point of view, I think without question there will be nuclear power in space flight. I think that there is a period now, of from 5 to 10 years of development during which time we most certainly will use chemical propellants.
Senator ANDERSON. I am only interested in trying to say that I do believe we ought to be considering nuclear flights, and there isn't any plan
Mr. SILVERSTEIN. We are certainly studying it.
Now, Senator Green asked something about international cooperation. What section of the bill permits international cooperation on space activities?
Dr. DOOLITTLE. There is none.
Senator ANDERSON. That's right, there is none. That's all, Mr. Chairman.
Senator GREEN. Thank you, Dr. Doolittle.
Senator SYMINGTON. I have no further questions, thank you, Mr. Chairman.
Senator GREEN. Dr. Doolittle, you are anxious to get away, I know. We want to thank you very heartily for your testimony here this morning, not only which related to space matters, but you were able to explain it to us very clearly.
The committee will recess now until 2:30 this afternoon, when it will receive testimony from the Chairman of the Atomic Energy Commission, Adm. Lewis Strauss.
(Whereupon, at 12:30 p. m., the hearing was recessed, until 2:30 p. m.,
of the same day.)
Senator JOHNSON. The committee will come to order.
Admiral Strauss, will you come to the table, please, and bring with you any of your associates that you desire to have participate in the hearing. Will you please identify them to the committee for the record.
Mr. STRAUSS. Thank you, Mr. Chairman. On my left, is Mr. Olsen, the General Counsel of the Atomic Energy Commission, Gen. Donald Keirn is in charge of the Air Reactors Branch of the Division of Reactor Development of the Commission, and Mr. Bryan Laplante, who is with the Office of Congressional Liaison.
Senator JOHNSON. Our next witness is Admiral Strauss, Chairman of the Atomic Energy Commission.
Admiral Strauss, the committee is looking forward with great interest to the testimony and recommendations you have to make to
It is obvious from the preliminary studies that have been done by our staff thus far that many of the plans for future exploration of outer space are based upon the discoveries that have heretofore been made in atomic energy.
As Chairman of this highly important Commission, you are fully qualified to discuss this question and shed light upon many of its ramifications.
As background for your testimony, and without objection, I should like to place a brief biographical sketch of Admiral Strauss in the record at this point. Without objection, it will be included in the record.
(The biographical sketch of Admiral Strauss is as follows:) BIOGRAPHY OF ADM. LEWIS L. STRAUSS, CHAIRMAN, ATOMIC ENERGY COMMISSION
Mr. Strauss was born in Charleston, W. Va., on January 31, 1896. He was educated in the public schools in Richmond and has received several honorary degrees from a number of universities.
He was secretary to Herbert Hoover, 1917-19, and was associated with Kuhn, Loeb & Co. from 1919–46. He was a member of the Atomic Energy Commission from 1946–50, and has been Chairman of the AEC since 1953. a lieutenant commander in the USNR from 1926, advanced to rear admiral 1945.
He has been awarded the Distinguished Service Medal, Legion of Merit, the Gold Star (Navy) and Oak Leaf Cluster.
The CHAIRMAN. Admiral Strauss, will you proceed in your own way to make any comments you desire in connection with the pending legislation or any observations or recommendations in this field that you think would be helpful to the committee, to the Nation, and to the world.
STATEMENT OF ADM. LEWIS L. STRAUSS, CHAIRMAN, ATOMIC
ENERGY COMMISSION; ACCOMPANIED BY LARRY OLSEN, GENERAL COUNSEL, AEC; GEN. DONALD KEIRN, IN CHARGE OF THE AIRCRAFT REACTORS BRANCH OF THE AEC, AND BRYAN LaPLANTE, SPECIAL ASSISTANT TO THE GENERAL MANAGER FOR CONGRESSIONAL LIAISON OF THE AEC
Mr. STRAUSS. Thank you, Senator Johnson.
This is the first opportunity that I have ever had to appear before you.
Senator JOHNSON. Admiral, these microphones are for the cameras. They are not loudspeakers, so you will have to speak a little louder. . I hope you have been able to hear me.
Mr. STRAUSS. I have heard you clearly, and if I am not making myself heard at the bench, I hope you will let me know.
I am glad to have an opportunity to testify on this important and timely legislation.
I have a very brief statement. It has been prepared only very recently; as a matter of fact it was completed within the hour, and unfortunately I do not have copies. I will attempt to provide them a little later.
Senator JOHNSON. Very well.
Mr. STRAUSS. It would appear, Mr. Chairman, and Senators, that we are rapidly entering, what, for want of a better description, is called the space age, and it will one day have an impact on our civilization which we can only speculate upon today.
As has been true in the case of atomic energy it seems inevitable that projected space efforts will open whole new horizons of human activity.
I believe the Atomic Energy Commission is appreciative of the importance of space activities demonstrated by our ROVER and SNAP programs which were initiated long before we had heard of sputniks.
I might explain, since these are code names for convenience, ROVER is the code name of the project under which the Atomic Energy Commission conducts its research and development on nuclear-powered propulsion rockets, and SNAP is the code name under which the Commission conducts similar research for the provision of nuclear power to be used aboard satellites.
If I use these words again, and I believe I do in the statement, ROVER is rockets, and SNAP is nuclear power for satellites.
Our national objective must be bold if the free world is to establish leadership in the conquest of space for peaceful purposes. Because of the newness of the field, effective progress will also require imaginative planning and aggressive execution.
In any forthright and daring endeavor such as this, however, we must expect some disappointments and failures along the way. These failures, of course, are rather more painful and visible in an open democracy than are similar difficulties which one can be reasonably sure also plague those behind the Iron Curtain.
Our goals must be carefully conceived and not permitted to fluctuate in response to emotional pressures engendered by the sporadic success of other nations or the momentary and inevitable occasional failures within our own program.
In view of these factors, it is most important that the legislation which is enacted in this area should provide for an effective and streamlined organization which will facilitate a vigorous national program.
The Commission concurs with the basic concepts expressed in Senate bill 3609 for civilian conduct of the research and development activities concerning civilian application of flight within and beyond the earth's atmosphere.
Equally important, the Atomic Energy Commission strongly supports the concentration in one agency of the overall planning and direction of our national space program.
In the absence of such central direction, we believe that our space activities will lag, our objectives will become confused and uncertain, and result in a costly duplication of efforts. It has been my own belief, and I have so testified, that the selection of the particular agency is perhaps less basic than a clear delineation of responsibility.
Although there are a number of ways in which this central direction might be achieved, it seems to me that Senate bill 3609 accomplishes this purpose effectively.
Although the bill provides for the concentration of overall responsibility which we regard as so essential, it also recognizes the fact
that other agencies, such as the Department of Defense, will continue to play a vital role in space exploration and development.
I am sure that the Atomic Energy Commission will also continue to make important contribution to our space future if the bill is enacted. It seems obvious that the highly specialized talent and experience which exist within the Atomic Energy Commission should not be duplicated by another agency. This is particularly true when one considers the shortage of available scientific manpower in the cross fertilization of ideas which is encouraged in the Commission's laboratories and with considerable success over the
years. Those members of your committee who are also members of the Joint Committee on Atomic Energy, are familiar with our ROVER and SNAP programs.
For the benefit of the other members of this committee, perhaps I might outline so far as possible in an open hearing, the role which atomic energy might reasonably expect to play in space exploration.
Might I point out that the mean distance to the far planets, Pluto, for example, is said to be well over 3 billion miles; 30 plus times as far as we are from the sun. If one assumes straigbt line travel at an average speed of about 25,000 miles per hour, it would require some 18 years for a one-way trip, a significant portion of man's life span.
On the other hand, the planet Mars, by comparison, is relatively close by. Under the same assumptions, it would require only about 83 days to make a similar trip, and a trip to the moon would require only about a half day.
So until considerable advances in propulsion are possible, it would appear that practical considerations would limit us to the shorter voyages noted above, and in this concept, tberefore, I would like to elaborate.
To reach, maneuver, and to explore space within our solar system, at least as far as Mars, one must consider possibly three thresholds of basic propulsion.
One threshold is that of earth escape. Another is that of navigation and maneuver, and the third is that of landing at a destination or back upon the earth.
First, one must leave the earth with its tremendous drag of gravity and air resistance, by means of a booster engine of relatively high thrust; with the further development of space exploration we will have to place more and more mass in orbit. Requirements for the transporting of instrumentation, of men, food, and equipment, will increase with the development of space technology.
Beyond certain payload and range limits, I am told that it may cease to be practical to use chemical propulsion and that nuclear propulsion, with its far greater energy potential, will probably have to be utilized.
I state this, however, as information, and naturally not on the basis of any calculation which I personally am qualified to make. I understand that current atomic reactor concepts, if proven workable, will provide greater performance capability than chemical systems. Yet these reactor concepts "tap” only a small fraction of available fission energy which can be converted to useful work and the potential for future nuclear systems would therefore seem to be large.
In this context, I might note that the energy release of fissioning 1 pound of uranium 235, if it were available, would be equivalent to something in the order of 2 million pounds of chemical fuel.
Once an object is placed in space by means of a high-thrust booster, the second threshold of propulsion must be considered. An object in orbit is free from any appreciable effect of gravity and air resistance, and extremely high thrust for relative movements is then no longer required. This is the area of the possible use of ion propulsion. Here again, nuclear power appears necessary. The thrust which an ionic device can impart may be quite small; yet even small thrust applied over a long period of time in space, free from the appreciable effects of gravity and air resistance, it is believed can impart the extremely high velocities that may be required for navigation.
The large quantities of electric power which are made necessary by the long period of time involved in ionic propulsion suggests the need for nuclear power systems.
The vehicle itself, the first of which would be unmanned in all likelihood, also has demands for electric power to activate its many possible accessories, such as television, recording devices, and other uses, and its capability to transmit this information back to earth must depend upon nuclear systems for power available over long periods of time.
The weights of such systems, then, become extremely important, for every pound of payload in orbit is multiplied many times in the weight of the system required to place it in orbit.
For instance, our staff has calculated that the need of 10 kilowatts of electric power, which is roughly equivalent to the horsepower rating of some of the small three-wheeled sports cars, would require about 15 tons of fuel, plus oxygen, in order for a vehicle to operate in space for only 30 days.
Many other schemes exist to furnish this power such as solar energy. However, they do not appear to our technicians to be as attractive as nuclear power for any reasonable range of power requirement that we can foresee and are not as yet so far developed as even nuclear power is for this purpose.
I spoke, Mr. Chairman, of a possible third threshold of propulsion, and this would be the area of retardation, which would allow survival landings on, say, the moon, or upon return to our earth.
This again could be a chemical system or a nuclear system, depending upon the mission to be performed. In fact, it is quite possible that in some missions, several combinations of nuclear and chemical systems might be employed.
I have reviewed these areas of space propulsion to indicate why the Commission believes that the Nation's space program will draw heavily on nuclear energy and, consequently, why we feel that the Commission will continue to play an indispensable role in our space future.
This, Mr. Chairman, concludes my formal comments on the bill. I would like, in closing, again to say that the Atomic Energy Com-. mission strongly supports its objectives.
QUESTION OF AUTHORITY FOR DIRECTION OF A SPACE PROGRAM
I believe you
Senator JOHNSON. Thank you for your statement. testified to the wisdom of giving control and direction and authority to one agency over our space program.