The Atomic Bomb Tests at Lake Sindorsk


MR. CHAIRMAN, Members of the Historical Society:— The descendants of George Sturtevant, a physicist employed during the middle years of the twentieth century by the State Department of the United States of America, have recently found a steel box containing documents of the greatest historical significance. These papers are copies of official reports submitted by Sturtevant to his principals in Washington while he was on a special mission in late 1946. Sturtevant had been sent to Moscow in connection with the Soviet atomic bomb test held New Year’s Day, 1947, near Lake Sindorsk, in the Komi S.S.R.

The existence of the Sturtevant reports had been unsuspected. Possibly the original copies received in Washington were purposely destroyed, or possibly the reports were accidentally lost. In any event, it is fortunate that the reports have now been found, for they shed new light on that vexing time, the opening of the atomic age.

There can be little doubt of the authenticity of these papers. They are written in full in Sturtevant’s own hand, and apparently constitute the original drafts prepared by Sturtevant for typing by an Embassy stenographer. At the foot of each document is noted the date on which it was transmitted to Washington. The papers were written with an early ball-pointed pen, as can readily be seen by an examination of the quality of line. Such pens were first generally sold in early 1946, and the composition of the writing fluid used was drastically altered only two years later.

My purpose tonight is not, however, to convince you of the reliability of the Sturtevant reports, nor to acquaint you with their full contents. A critical edition of the reports will soon be published. Tonight I wish simply to point out the major new historical conclusion to which these documents bring us. I must apologize for reminding you, then, of the pertinent events of the year 1946.

In that year, you will remember, the two most powerful states of the world were the United States of America and Russia. There were half a hundred other autonomous nations, including giant rural countries like China, and nations past the zenith of their power, like Great Britain. All these nations, or nearly all, were joined together in a loose confederation called the United Nations, whose formation had rested on the agreement to maintain the right of a single powerful state to block joint action desired by all the others. For the nations were distrustful of one another and jealous of world power. The United States and Russia knew that each need fear only the other, of all the nations in the world.

More than any other cause, man’s winning of atomic energy led to the disquiet of that time. The power of the atom had then been used only for destruction. World War II (1939-1945) had been ended by the explosion of two atomic bombs dropped without warning on the Japanese homeland by aircraft of the United States. At the end of 1945, American atomic-energy policy began to develop along two divergent paths.

On the one hand, the United States made to the other nations of the world quite reasonable proposals, by the standards of the time. These proposals were aimed toward the international control of atomic energy for peace, so that the threat of atomic war would be abated and the benefits of atomic power might be available equally to all. On the other hand, the interim control of atomic energy was kept entirely in the hands of the Army, whose policy was based on the idea that it would soon be necessary to fight an atomic war. The strictest secrecy regarding all phases of atomic energy was rigidly maintained. A bill for the Federal control of atomic energy, worked out by the Senate of the United States, had not yet passed Congress when, in the far Pacific, the Bikini Tests were held (July, 1946).

Two atomic bombs were exploded in the Bikini Tests, one a few hundred feet in the air and the other just under the surface of the sea. About the point of each explosion were disposed a number of warships at anchor. The stated purpose of the tests was to determine the degree of resistance to an atomic explosion offered by all types of military and naval equipment. Without examining the strategical effect of atomic explosives on warfare, the people of that time were concerned with the detailed problem of whether the Army and Navy matèriel they had used in the war just past retained any tactical suitability in the war they felt might soon come.


MEANWHILE, the Russians had been working hard. Molotov, then Foreign Minister, had said in late 1945: “We will have atomic energy, and many other things.” American estimates of the time required for the Russians to develop atomic bombs varied from a minimum of three to five years to the “more than a generation” which a general officer of the United States Army, prominent in the early days of the atomic energy project, allowed himself to predict.

Shortly after the completion of the Bikini Tests, the United States government began to suspect that the Russians were planning a test of an atomic bomb which they themselves had made. Long before there was any public announcement, William T. Harrison, an attaché of the United States Embassy in Moscow, heard from Russian scientists of his acquaintance rumors that led him to believe in such a possibility. On the basis of Harrison’s reports, George Sturtevant was sent to Moscow with the task of learning all he could about Russian knowledge of the bomb.

Sturtevant’s first nine weeks in Moscow wore unproductive. Then came the first official Russian announcement. It said that scientists of the U.S.S.R. had mastered the technique of releasing atomic energy, that large power plants would soon be erected in various parts of the Soviet Union where fuel and waterpower were scarce, and that Russia planned to concentrate on the development of atomic energy for peaceful purposes.

However, the announcement went on to say, Russia would follow the United States lead in keeping entirely secret everything it knew about atomic energy, lest some country less disposed toward peace should endanger the security of the world by learning how to make atomic bombs. The ever present threat of this occurrence, despite the most stringent precautions, had forced the Soviet Union to decide to lay up a supply of atomic bombs as a defense against a possible fascist aggressor.

The first bomb had been completed for some time, and it would be exploded to enable measurements of its effectiveness in terms of blast, heat, radiation, and total energy release. Calculations of Soviet Academicians indicated that the Russian bomb was quite comparable to the United States “Nagasaki” weapon, which employed plutonium as an explosive, but such theoretical considerations always must be checked by trials.

The explosion would be held January 1, 1947 (the announcement continued), or as soon thereafter as weather conditions were favorable. The site selected was in the foothills of the Timan Mountains, near Sindorsk Lake, in the Komi S.S.R. The bomb would be set off just at the surface of the earth, or a little above the surface. Elaborate instrumentation would be provided to measure all the interesting quantities — pressure, temperature, ionization, radioactivity, and so on.

Arrangements were being made for world-wide news coverage of the event, both by press and radio. Every country of the United Nations was invited to send an observer, but because of the great difficulty involved in the arrangements, only one representative would be permitted each foreign nation. Of course, the results of the test could not be published in detail, but as much as security permitted would be made public.

Today, we can scarcely appreciate the excitement, confusion, even hysteria, which this announcement produced in the United States. Large numbers of the American people felt that a war between the United States and Russia was inevitable, because of the fundamental difference in their respective philosophies of government, if for no other reason. Everyone understood that the United States was far more vulnerable to atomic attack than Russia, because of America’s much greater centralization of industry and population. And the degree to which the attacker in an atomic war held the advantage was fully appreciated.

Streamer headlines as big as those which had heralded the end of the war less than two years before carried news of the Russian announcement, and the editorial columns were devoted almost altogether to interpreting it in terms of the national interest of the United States Interpretations ranged all the way from the conclusion that “preventive” war should be commenced at once, to the quiet remark that this Russian development simply underlined the need for an immediate world-wide agreement to outlaw the dangerous uses of atomic energy, and thus might assist in reducing the areas of disagreement existing between nations regarding such control.


IN a few days, uncritical acceptance of the Russian announcement gave way to partial skepticism. Americans had been told by their scientists that anyone could unlock the secret of the atom, but they had also been told, by others, that no other country had the “know-how” (a barbarism of the time, meaning technical ability) to do the job. Many believed it unlikely that the Russians really possessed the knowledge and the physical plant necessary to make atomic bombs so soon after the United States had made its first disclosure that this could be done. There was a growing feeling that the Soviet news release might be a hoax.

Sturtevant, of course, was aware of the possibility that the Soviet claims were false, and almost his entire effort, once the original press release had been made, was devoted to attempting to discover whether or not a real atomic bomb was to be exploded in the Sindorsk Test, as it had come to be known. The interest of his principals in Washington was also concentrated on finding whether or not the Russian claims should be taken at their face value. An abridgment of the first report submitted by Sturtevant after the announcement of the Sindorsk Test shows how clearly he grasped the issues: —

“In what follows I indicate the lines along which it might be discovered whether or not the bomb to be used in the Sindorsk Test is a true atomic bomb. If the announcement is a hoax, the explosion of an atomic bomb must be counterfeited in a way which can deceive those attending the test. This deception will be made easier by the fact that the nearest foreign observer will be at least eight miles from the point of the explosion, and may be considerably farther away.

“What are the properties which characterize the explosion of an atomic bomb? These properties are the ones that must be faked if the Russian announcement is false.

“First, of course, is the appearance of the cloud which rises over the explosion. The ‘mushroom’ that is typical of an atomic bomb burst is now quite familiar. It may be less well known that a highorder detonation of any quantity of high explosive greater than about 3000 tons will produce such a ‘mushroom.’ Thus we cannot rely on the formation of a ‘mushroom’ as an index of the atomic character of the bomb.

“The energy release in the explosion of an atomic bomb is, of course, enormous. It is in the neighborhood of that produced by the explosion of 20,000 tons of TNT. This, however, is no help; for the actual explosion of 20,000 tons of TNT, if a highorder detonation is achieved by careful fuzing or otherwise, would counterfeit the release of energy required and the necessary blast pressures. When it is considered that 50,000 tons of TNT would occupy a cubical space only 100 feet on an edge, the feasibility of using ordinary chemical explosives to produce such a gigantic explosion becomes clear. The only lead this suggests is to try to trace the activities of the Soviet experts on high explosives.

“The detonation of a quantity of ordinary high explosive would not produce the great light intensities characterizing an atomic bomb explosion, without special attention to this detail. However, the addition to the explosive of suitable quantities of powdered magnesium and aluminum would probably produce a flash great enough to deceive observers at a distance of several miles, especially when they are wearing dark glasses and lying down with their feet toward the bomb. It would be necessary to add to the explosive suitable substances to maintain the luminosity of the cloud, but this can probably be done.

“Another characteristic of the explosion of an atomic bomb is the radioactivity produced. The radioactive cloud resulting from the Alamogordo Test of July last year was detectable in Washington, D.C., when the winds carried it there. It might be hoped that we could detect the presence or absence of such a cloud by means of instruments for the measurement of radiation if we placed them as near as we could to the test site. Our nearest consulate, however, is almost a thousand miles from the point at which this explosion will occur, and it will always be possible for the Russians to claim (as they will certainly do if the test is a hoax) that rainstorms occurring immediately after the test brought most of the radioactivity down to earth.

“Also, they can certainly assemble enough radium and other naturally occurring radioactive substances to render the area directly under the point of explosion quite active. No doubt, observers will be forbidden to enter this area until ‘the original very strong radioactivity has decayed to a safe level’ (which is good practice, even if the test is honest). It will probably then be impossible to detect whether the residual radioactivity is that of artificial or natural radioelements, without the use of elaborate equipment which the Russians will certainly not permit to foreign observers.

“The only aspect of an atomic bomb explosion which is both difficult to counterfeit and possible to observe without elaborate apparatus — so far as I can see — is the blue glow, due to ionization of the air, which surrounds the ‘ball of fire’ and the cloud from the explosion in its earliest stages. This glow is due to radioactivity so strong that it cannot be imitated by dispersing radium in the high explosive which is used to produce the fake ‘atomic’ explosion; and I have not been able to think of any way in which this glow could be counterfeited.

“I cannot overemphasize the importance of sending to the Sindorsk Test, as the American observer, a physicist with wide experience in the observation of atomic bomb explosions. I myself would possess the necessary qualifications, but I suppose that a more prominent scientist would be easier to explain as a choice. On no account should a non-physicist be sent. If I fail to unearth anything decisive in my work here in Moscow, our entire knowledge of the validity of the Russian announcement may rest on a few seconds’ observation by the one man the Russians will permit us to send to the test.”


NEARLY three months remained between the date of this dispatch from Sturtevant and the day set for the Sindorsk blast. In this time, Sturtevant made vigorous efforts to find some definite evidence confirming or disproving the Russian claims that they had mastered atomic energy. A crew of American economic experts and mining engineers did discover that known ore deposits containing uranium were being intensively worked by the Russians, and that new deposits were being widely prospected for in the U.S.S.R., but these things would have been done in any case. Of the foremost Russian explosives men, two had disappeared from their usual residences and occupations; but Sturtevant knew that an atomic bomb of the type familiar to him presented some rather novel pyrotechnic problems, and therefore refrained from forming a judgment on this bit of evidence.

Meanwhile, it will be remembered, popular hysteria in the United States and in England had resulted in the lynching of several scientists suspected of giving atomic bomb secrets to Russia.

A month before the test, at a time when the United States had still not named its representative at the great show, Sturtevant sent back to Washington a report which said, in part: —

“I regret to report that the intelligence activities which have been carried on here in Moscow have been entirely inconclusive. There appears to be a strong possibility that the Russians are working an elaborate bluff, and that the explosion of their ‘atomic’ bomb may be a fake, conducted by amassing a suitable quantity of chemical explosive. On the other hand, there is nothing which indicates definitely that their claims are false.

“Under these conditions, as emphasized in my first report after the Russian announcement, the greatest importance attaches to the selection of the American observer who is to be sent to witness the Sindorsk Test. He should be a physicist of the highest competence, and one who has observed two or more explosions of true atomic bombs. Only in his ability to detect the presence or absence of the blue ionization glow surrounding the explosion in its earliest stages can we hope for a valid assessment of the Russian claims.”

Despite this clear statement from Sturtevant, the United States government yielded to political pressure in the choice of its official observer for the Russian test. The important official who was selected had been present at one of the United States atomic bomb demonstrations, and had taken a very considerable part in early United States affairs connected with atomic energy. He did not pretend to sufficient scientific competence, however, to enable him to make certain detailed observations suggested by Sturtevant, such as examining the spectrum of the light from the explosion by means of an inconspicuous transmission-type diffraction grating cemented to a pair of eyeglasses.

Sturtevant, of course, was appalled by this decision. During the thirty-six-hour stay of the official observer in Moscow, Sturtevant attempted to talk with him, but the necessities of official entertainment did not permit them to get together. Sturtevant contented himself with the preparation of a long memorandum outlining what to look for at the moment of the explosion, which he delivered to the official observer’s aide.

What actually happened at Sindorsk will probably never be known. The observer’s well-known official report makes it clear, in the light of the Sturtevant reports, that his observation of events immediately after the explosion was not sufficiently careful to make a decision possible on the blue glow. The French observer, who was located near-by, said later that the United States observer was in a considerable state of excitement. He got to his feet, the Frenchman said, immediately after the explosion, without taking off his dark glasses, and was knocked down some seconds later by the arrival of the blast wave.

The United States, British, and French observers had been put as close as possible to the actual point of explosion, as a mark of extraordinary respect.

The United States observer’s report was unequivocal in describing the Russian explosion as that of a true atomic bomb. This decision has been accepted ever since. It seems, however, that there was no circumstantial account of evidence which convinced Sturtevant of the truth of this judgment. Sturtevant’s evaluation of the official report, a masterpiece of self-control, says merely: —

“There is no convincing evidence in the report of the official United States observer at the Sindorsk Test which enables a decision to be made on whether the Russians really set off an atomic bomb. The blue glow which I believe to be the only decisive evidence is described in the following terms: ‘The manycolored cloud ascended above the point of explosion, and soon took on the mushroom-shaped appearance characteristic of an atomic bomb explosion.’

“I have had the opportunity of speaking with the official observer, and find that he is not certain whether or not there was such a glow. The photographs released by the Russians show a nimbus about the explosion cloud which might correspond to this phenomenon, but they would certainly retouch the photographic negatives to give this appearance, if the test were really a hoax.

“No decision as to the validity of the Russian assertions about their progress in atomic energy seems to be possible without further intelligence work.”

Thus, the United States authorities were entirely without knowledge of the truth of the Russian claims, even after the great test at Sindorsk. As is well known, their course of action in this crisis was decided upon only a few days later. The interesting fact revealed for the first time by the Sturtevant reports is that this action was taken in complete ignorance of the state of atomic energy development in Russia.