by Fred Hoyle
The Black Cloud
Fred Hoyle
Fred Hoyle
The Black Cloud
With an Afterword by Richard Dawkins
PENGUIN BOOKS
PENGUIN CLASSICS
Published by the Penguin Group
First published by Heinemann 1957
Preface
I hope that my scientific colleagues will enjoy this frolic. After all, there is very little here that could not conceivably happen.
Since institutional posts that actually exist are mentioned in the story, I have been at particular pains to ensure that the associated characters have no reference to actual holders of these posts.
It is commonplace to identify opinions forcibly expressed by a character with the author’s own. At the risk of triviality, I would add that this association may be unwarranted.
F. H.
Prologue
The episode of the Black Cloud has always had a great fascination for me. The thesis that won me my Fellowship at Queens’ College, Cambridge, was concerned with some aspects of this epic event. This work was later published, after suitable modifications, as a chapter in Sir Henry Clayton’s History of the Black Cloud, much to my gratification.
It was not altogether surprising therefore that Sir John McNeil, our late Senior Fellow and well-known physician, should have willed to me on his death a voluminous collection of papers dealing with his own personal experiences of the Cloud. More surprising, however, was the letter that accompanied the papers. It read:
Queens’ College,
19 August 2020
My dear Blythe,
I trust you will forgive an old man for chuckling occasionally to himself over some of your speculations concerning the Black Cloud. As it happened, I was so placed during the crisis that I learned of the real nature of the Cloud. This information for various cogent reasons has never been made public and seems unknown to the writers of official histories (sic!). It has caused me much anxiety of mind to decide whether my knowledge should pass away with me or not. In the event I have decided to hand on my difficulties and uncertainties to you. These will I believe become clearer to you when you have read my MS., which, incidentally, I have written in the third person so that I myself do not obtrude too much on the story!
In addition to the MS., I am leaving you an envelope containing a roll of punched paper tape. I beg you to guard this tape with the greatest care until you come to understand its significance.
Sincerely,
John McNeil
Opening Scenes
It was eight o’clock along the Greenwich meridian. In England the wintry sun of 7 January 1964 was just rising. Throughout the length and breadth of the land people were shivering in ill-heated houses as they read the morning papers, ate their breakfasts, and grumbled about the weather, which, truth to tell, had been appalling of late.
The Greenwich meridian southward passes through western France over the snow-covered Pyrenees, and through the eastern corner of Spain. The line then sweeps to the west of the Balearic Islands, where wise people from the north were spending winter holidays — on a beach in Minorca a laughing party might have been seen returning from an early morning bathe. And so to North Africa and the Sahara.
The primary meridian then swings towards the equator through French Sudan, Ashanti, and the Gold Coast, where new aluminium plants were going up along the Volta River. Thence into a vast stretch of ocean, unbroken until Antarctica is reached. Expeditions from a dozen nations were rubbing elbows with each other there.
All the land to the east of this line, as far as New Zealand, was turned towards the Sun. In Australia, evening was approaching. Long shadows were cast across the cricket ground at Sydney. The last overs of the day were being bowled in a match between New South Wales and Queensland. In Java, fishermen were busying themselves in preparation for the coming night’s work.
Over much of the huge expanse of the Pacific, over America, and over the Atlantic it was night. It was three a.m. in New York. The city was blazing with light, and there was still a good deal of traffic in spite of recent snow and a cold wind from the northwest. And nowhere on the Earth at that moment was there more activity than in Los Angeles. The evening was well along there, midnight: the boulevards were crowded, cars raced along the freeways, restaurants were still pretty full.
A hundred and twenty miles to the south the astronomers on Palomar Mountain had already begun their night’s work. But although the night was clear and stars were sparkling from horizon to zenith, conditions from the point of view of the professional astronomer were poor, the ‘seeing’ was bad — there was too much wind at high levels. So nobody was sorry to down tools for the midnight snack. Earlier in the evening, when the outlook for the night already looked pretty dubious, they had agreed to meet in the dome of the 48-inch Schmidt.
Paul Rogers walked the four hundred yards or so from the 200-inch telescope to the Schmidt, only to find Bert Emerson was already at work on a bowl of soup. Andy and Jim, the night assistants, were busy at the cooking stove.
“Sorry I got started,” said Emerson, “but it looks as though tonight’s going to be a complete write-off.”
Emerson was working on a special survey of the sky, and only good observing conditions were suitable for his work.
“Bert, you’re a lucky fellow. It looks as though you’re going to get another early night.”
“I’ll keep on for another hour or so. Then if there’s no improvement I’ll turn in.”
“Soup, bread and jam, sardines, and coffee,” said Andy. “What’ll you have?”
“A bowl of soup and cup of coffee, thanks,” said Rogers.
“What’re you going to do on the 200-inch? Use the jiggle camera?”
“Yes, I can get along tonight pretty well. There’s several transfers that I want to get done.”
They were interrupted by Knut Jensen, who had walked the somewhat greater distance from the 18-inch Schmidt.
He was greeted by Emerson.
“Hello, Knut, there’s soup, bread and jam, sardines, and Andy’s coffee.”
“I think I’ll start with soup and sardines, please.”
The young Norwegian, who was a bit of a leg-puller, took a bowl of cream of tomato, and proceeded to empty half a dozen sardines into it. The others looked on in astonishment.
“Judas, the boy must be hungry,” said Jim.
Knut looked up, apparently in some surprise.
“You don’t eat sardines like this? Ah, then you don’t know the real way to eat sardines. Try it, you’ll like it.”
Then having created something of an effect, he added:
“I thought I smelled a skunk around just before I came in.”
“Should go well with that concoction you’re eating, Knut,” said Rogers.
When the laugh had died away, Jim asked:
“Did you hear about the skunk we had a fortnight ago? He de-gassed himself near the 200-inch air intake. Before anybody could stop the pump the place was full of the stuff. It sure was some hundred per cent stink. There must have been the best part of two hundred visitors inside the dome at the time.”
“Lucky we don’t charge for admission,” chuckled Emerson, “otherwise the Observatory’d be sunk in for compensation.”
“But unlucky for the clothes cleaners,” added Rogers.
On the way back to the 18-inch Schmidt, Jensen stood listening to the wind in the trees on the north side of the mountain. Similarities to his native hills set off an irrepressible wave of homesickness, longing to be with his family again, longing to be with Greta. At twenty-four, he was in the United States on a two-year studentship. He walked on, trying to kick himself out of what he felt to be a ridiculous mood. Rationally he had no cau
se whatsoever to be dispirited. Everyone treated him with great kindness, and he had a job ideally suited to a beginner.
Astronomy is kind in its treatment of the beginner. There are many jobs to be done, jobs that can lead to important results but which do not require great experience. Jensen’s was one of these. He was searching for novae, stars that explode with uncanny violence. Within the next year he might reasonably hope to find one or two. Since there was no telling when an outburst might occur, nor where in the sky the exploding star might be situated, the only thing to do was to keep on photographing the whole sky, night after night, month after month. Some day he would strike lucky. It was true that, should he find a nova located not too far away in the depths of space, then more experienced hands than his would take over the work. Instead of the 18-inch Schmidt, the full power of the great 200-inch would then be directed to revealing the spectacular secrets of these strange stars. But at all events he would have the honour of first discovery. And the experience he was gaining in the world’s greatest observatory would stand well in his favour when he returned home — there were good hopes of a job. Then he and Greta could get married. So what on earth was he worried about? He cursed himself for a fool to be unnerved by a wind on the mountainside.
By this time he had reached the hut where the little Schmidt was housed. Letting himself in, he first consulted his notebook to find the next section of the sky due to be photographed. Then he set the appropriate direction, south of the constellation of Orion: mid-winter was the only time of the year when this particular region could be reached. The next step was to start the exposure. All that remained was to wait until the alarm clock should signal its end. There was nothing to do except sit waiting in the dark, to let his mind wander where it listed.
Jensen worked through to dawn, following one exposure with another. Even so his work was not at an end. He had still to develop the plates that had accumulated during the night. This needed careful attention. A slip at this stage would lose much hard work, and was not to be thought of.
Normally he would have been spared this last exacting task. Normally he would have retired to the dormitory, slept for five or six hours, breakfasted at noon, and only then would he have tackled the developing job. But this was the end of his ‘run’. The moon was now rising in the evening, and this meant the end of observing for a fortnight, since the nova search could not be carried on during the half of the month when the moon was in the night sky — it was simply that the moon gave so much light that the sensitive plates he was using would have been hopelessly fogged.
So on this particular day he would be returning to the Observatory offices in Pasadena, 125 miles away. The transport to Pasadena left at half past eleven, and the developing must be done before then. Jensen decided that it would be best done immediately. Then he would have four hours’ sleep, a quick breakfast, and be ready for the trip back to town.
It worked out as he had planned, but it was a very tired young man who travelled north that day in the Observatory transport. There were three of them: the driver, Rogers, and Jensen. Emerson’s run had still another two nights to go. Jensen’s friends in wind-blown, snow-wrapped Norway would have been surprised to learn that he slept as the car sped through the miles of orange groves that flanked the road.
Jensen slept late the following morning and it wasn’t until eleven that he reached the Observatory offices. He had about a week’s work in front of him, examining the plates taken during the last fortnight. What he had to do was to compare his latest observations with the other plate that he had taken in the previous month. And this he had to do separately for each bit of the sky.
So, late on this morning of 8 January 1964, Jensen was down in the basement of the Observatory buildings setting up an instrument known as the ‘blinker’. As its name implies, the ‘blinker’ was a device that enabled him to look first at one plate, then at the other, then back to the first one again, and so on in fairly rapid succession. When this was done, any star that had changed appreciably during the time interval between the taking of the two plates stood out as an oscillating or ‘blinking’ point of light, while on the other hand the vast majority of stars that had not changed remained quite steady. In this way it was possible to pick out with comparative ease the one star in ten thousand or so that had changed. Enormous labour was therefore saved because every single star did not have to be examined separately.
Great care was needed in preparing plates for use in the ‘blinker’. They must not only be taken with the same instrument, but so far as possible must be shot under identical conditions. They must have the same exposure times and their development must be as similar as the observing astronomer can contrive. This explains why Jensen had been so careful about his exposures and development.
His difficulty now was that exploding stars are not the only sort to show changes. Although the great majority of stars do not change, there are a number of brands of oscillating stars, all of which ‘blink’ in the manner just described. Such ordinary oscillators had to be checked separately and eliminated from the search. Jensen had estimated that he would probably have to check and eliminate the best part of ten thousand ordinary oscillators before he found one nova. Mostly he would reject a ‘blinker’ after a short examination, but sometimes there were doubtful cases. Then he would have to resort to a star catalogue, and this meant measuring up the exact position of the star in question. So all in all there was quite a bit of work to do before he got through his pile of plates — work that was not a little tedious.
By 14 January he had nearly finished the whole pile. In the evening he decided to go back to the Observatory. The afternoon he had spent at the California Institute of Technology, where there had been an interesting seminar on the subject of the spiral arms of the galaxies. There had been quite a discussion after the seminar. Indeed he and his friends had argued throughout dinner about it and during the drive back to the Observatory. He reckoned he would just about get through the last batch of plates, the ones he had taken on the night of 7 January.
He finished the first of the batch. It turned out a finicking job. Once again, every one of the ‘possibilities’ resolved into an ordinary, known oscillator. He would be glad when the job was done. Better to be on the mountain at the end of a telescope than straining his eyes with this damned instrument, he thought, as he bent down to the eye-piece. He pressed the switch and the second pair flashed up in the field of view. An instant later Jensen was fumbling at the plates, pulling them out of their holders. He took them over to the light, examined them for a long time, then replaced them in the ‘blinker’ and switched on again. In a rich star field was a large, almost exactly circular, dark patch. But it was the ring of stars surrounding the patch that he found so astonishing. There they were, oscillating, blinking, all of them. Why? He could think of no satisfactory answer to the question, for he had never seen or heard of anything like this before.
Jensen found himself unable to continue with the job. He was too excited about this singular discovery. He felt he simply must talk to someone about it. The obvious man of course was Dr Marlowe, one of the senior staff members. Most astronomers specialize on one or other of the many facets of their subject. Marlowe had his specialities too, but he was above all a man of immense general knowledge. Perhaps because of this he made fewer mistakes than most people. He was ready to talk astronomy at all hours of the day and night, and he would talk with intense enthusiasm to anyone, whether a distinguished scientist like himself or a young man at the threshold of his career. It was natural therefore that Jensen should wish to tell Marlowe about his curious find.
He carefully put the two plates in question in a box, switched off the electrical equipment and the lights in the basement, and made his way to the notice board outside the library. The next step was to consult the observing list. He found to his satisfaction that Marlowe was not away either at Palomar or Mount Wilson. But, of course, he might have gone out for the evening. Jensen’s luck was in
, however, for a phone call soon elicited that Marlowe was at home. When he explained that he wanted to talk to him about something queer that had turned up, Marlowe said:
“Come right over, Knut, I’ll be expecting you. No, it’s all right. I wasn’t doing anything particular.”
It says much for Jensen’s state of mind that he rang for a taxi to take him to Marlowe’s house. A student with an annual emolument of two thousand dollars does not normally travel by taxi. This was particularly so in Jensen’s case. Economy was important to him because he wished to travel around the different observatories in the United States before he returned to Norway, and he had presents to buy, too. But on this occasion the matter of money never entered his head. He rode up to Altadena, clutching his box of plates, and wondered whether in some way he’d made a fool of himself. Had he made some stupid mistake?
Marlowe was waiting.
“Come right in,” he said. “Have a drink. You take it strong in Norway, don’t you?”
Knut smiled.
“Not so strong as you take it, Dr Marlowe.”
Marlowe motioned Jensen to an easy chair by the log fire (so beloved by many who live in centrally heated houses), and after moving a large cat from a second chair, sat down himself.
“Lucky you rang, Knut. My wife’s out for the evening, and I was wondering what to do with myself.”
Then, typically, he plunged straight to the issue — diplomacy and political finesse were unknown to him.
“Well, what’ve you got there?’ he said, nodding at the yellow box that Jensen had brought.
Somewhat sheepishly, Knut took out the first of his two pictures, one taken on 9 December 1963, and handed it over without comment. He was soon gratified by the reaction.
“My God!’ exclaimed Marlowe. “Taken with the 18-inch, I expect. Yes, I see you’ve got it marked on the side of the plate.”
