The Black Cloud

by Fred Hoyle; Fred Hoyle

  ‘It’s too late to worry about that now,’ said the Director. ‘Our next step must be to measure the speed with which the cloud is moving towards us. Marlowe and I have had a long talk about it, and we think it should be possible. Stars on the fringe of the cloud are partially obscured, as the plates taken by Marlowe last night show. Their spectrum should show absorption lines due to the cloud, and the Doppler shift will give us the speed.’

  ‘Then it should be possible to calculate how long the cloud will be before it reaches us,’ joined in Barnett. ‘I must say I don’t like the look of things. The way the cloud has increased its angular diameter during the last twenty years makes it look as if it’ll be on top of us within fifty or sixty years. How long do you think it’ll take to get a Doppler shift?’

  ‘Perhaps about a week. It shouldn’t be a difficult job.’

  ‘Sorry I don’t understand all this,’ broke in Weichart. ‘I don’t see why you need the speed of the cloud. You can calculate straight away how long the cloud is going to take to reach us. Here, let me do it. My guess is that the answer will turn out at much less than fifty years.’

  For the second time Weichart left his seat, went to the blackboard, and cleaned off his previous drawings.

  ‘Could we have Jensen’s two slides again please?’

  When Emerson had flashed them up, first one and then the other, Weichart asked: ‘Could you estimate how much larger the cloud is in the second slide?’

  ‘I would say about five per cent larger. It may be a little more or a little less, but certainly not very far away from that,’ answered Marlowe.

  ‘Right,’ Weichart continued, ‘let’s begin by defining a few symbols.’

  Then followed a somewhat lengthy calculation at the end of which Weichart announced:

  ‘And so you see that the black cloud will be here by August 1965, or possibly sooner if some of the present estimates have to be corrected.’

  Then he stood back from the blackboard, checking through his mathematical argument.

  ‘It certainly looks all right – very straightforward in fact,’ said Marlowe, putting out great volumes of smoke.*

  ‘Yes, it seems unimpeachably correct,’ answered Weichart.

  At the end of Weichart’s astonishing calculation, the Director had thought it wise to caution the whole meeting to secrecy. Whether they were right or wrong, no good could come of talking outside the Observatory, not even at home. Once the spark was struck the story would spread like wildfire, and would be in the papers in next to no time. The Director had never had any cause to think highly of newspaper reporters, particularly of their scientific accuracy.

  From midday to two o’clock he sat alone in his office, wrestling with the most difficult situation he had ever experienced. It was utterly antipathetic to his nature to announce any result or to take steps on the basis of a result until it had been repeatedly checked and cross-checked. Yet would it be right for him to maintain silence for a fortnight or more? It would be two or three weeks at least before every facet of the matter were fully investigated. Could he afford the time? For perhaps the tenth time he worked through Weichart’s argument. He could see no flaw in it.

  At length he called in his secretary.

  ‘Please will you ask Caltech to fix me a seat on the night plane to Washington, the one that leaves about nine o’clock? Then get Dr Ferguson on the phone.’

  James Ferguson was a big noise in the National Science Foundation, controlling all the activities of the Foundation in physics, astronomy, and mathematics. He had been much surprised at Herrick’s phone call of the previous day. It was quite unlike Herrick to fix appointments at one day’s notice.

  ‘I can’t imagine what can have bitten Herrick,’ he told his wife at breakfast, ‘to come chasing over to Washington like this. He was quite insistent about it. Sounded agitated, so I said I’d pick him up at the airport.’

  ‘Well, an occasional mystery is good for the system,’ said his wife. ‘You’ll know soon enough.’

  On the way from the airport to the city, Herrick would commit himself to nothing but conventional trivialities. It was not until he was in Ferguson’s office that he came to the issue.

  ‘There’s no danger of us being overheard, I suppose?’

  ‘Goodness, man, is it as serious as that? Wait a minute.’

  Ferguson lifted the phone.

  ‘Amy, will you please see that I’m not interrupted – no, no phone calls – well, perhaps for an hour, perhaps two, I don’t know.’

  Quietly and logically Herrick then explained the situation. When Ferguson had spent some time looking at the photographs, Herrick said:

  ‘You see the predicament. If we announce the business and we turn out to be wrong, then we shall look awful fools. If we spend a month testing all the details and it turns out that we are right, then we should be blamed for procrastination and delay.’

  ‘You certainly would, like an old hen sitting on a bad egg.’

  ‘Well, James, I thought you have had a great deal of experience in dealing with people. I felt you were someone I could turn to for advice. What do you suggest I should do?’

  Ferguson was silent for a little while. Then he said:

  ‘I can see that this may turn out to be a grave matter. And I don’t like taking grave decisions any more than you do, Dick, certainly not on the spur of the moment. What I suggest is this. Go back to your hotel and sleep through the afternoon – I don’t expect you had much sleep last night. We can meet again for an early dinner, and by then I’ll have had an opportunity to think things over. I’ll try to reach some conclusion.’

  Ferguson was as good as his word. When he and Herrick had started their evening meal, in a quiet restaurant of his choice, Ferguson began:

  ‘I think I’ve got things sorted out fairly well. It doesn’t seem to me to make sense wasting another month in making sure of your position. The case seems to be very sound as it is, and you can never be quite certain – it would be a matter of converting a ninety-nine per cent certainty into a ninety-nine point nine per cent certainty. And that isn’t worth the loss of time. On the other hand you are ill-prepared to go to the White House just at the moment. According to your own account you and your men have spent less than a day on the job so far. Surely there are a good many other things you might get ideas about. More exactly, how long is it going to take the cloud to get here? What will its effects be when it does get here? That sort of question.

  ‘My advice is to go straight back to Pasadena, get your team together, and aim to write a report within a week, setting out the situation as you see it. Get all your men to sign it – so that there’s no question of the tale getting around of a mad Director. And then come back to Washington.

  ‘In the meantime I’ll get things moving at this end. It isn’t a bit of good in a case like this starting at the bottom by whispering into the ear of some Congressman. The only thing to do is to go straight to the President. I’ll try to smooth your path there.’

  A Meeting in London

  Four days earlier in London a remarkable meeting had been held in the rooms of the Royal Astronomical Society. The meeting had been called, not by the Royal Astronomical Society itself, but by the British Astronomical Association, an association essentially of amateur astronomers.

  Chris Kingsley, Professor of Astronomy in the University of Cambridge, travelled by train in the early afternoon to London for the meeting. It was unusual for him, the most theoretical of theoreticians, to be attending a meeting of amateur observers. But there had been rumours of unaccounted discrepancies in the positions of the planets Jupiter and Saturn. Kingsley didn’t believe it, but he felt that scepticism should rest on solid ground, so he ought to hear what the chaps had to say about it.

  When he arrived at Burlington House in time for the four o’clock tea, he was surprised to see that quite a number of other professionals had already arrived, including the Astronomer Royal. ‘Never heard of anything like this befo
re at the B.A.A. The rumours must have been put around by some new publicity agent,’ he thought to himself.

  When Kingsley went in to the meeting room some half hour later he saw a vacant place on the front row by the Astronomer Royal. No sooner had he sat down than a Dr Oldroyd who was in the chair began the meeting in the following terms:

  ‘Ladies and gentlemen, we meet here today to discuss some new and exciting results. But before I call on the first speaker I would like to say how pleased we are to see so many distinguished visitors. I am confident they will find that the time they have consented to spend with us will not have been wasted, and I feel that the important role of the amateur in astronomy will be demonstrated yet once again.’

  At this Kingsley grinned inwardly to himself, and several of the other professionals squirmed in their seats. Dr Oldroyd went on:

  ‘I have great pleasure in asking Mr George Green to address us.’

  Mr George Green jumped up from his seat half-way down the room. He then bustled forward to the rostrum, clutching a large pile of papers in his right hand.

  For the first ten minutes Kingsley listened with polite attention as Mr Green showed slides of his private telescopic equipment. But when the ten minutes lengthened to a quarter of an hour he began to fidget, and for the next half hour he lived in torment, first crossing his legs one way, then the other, then squirming round every minute or so to look at the clock on the wall. It was all in vain, for Mr George Green went right ahead with the bit firmly between his teeth. The Astronomer Royal kept glancing at Kingsley, a quiet smile on his face. The other professionals hugged themselves with delight. Their eyes never left Kingsley. They were calculating when the outburst would come.

  The outburst never came, for Mr Green suddenly seemed to remember the purpose of his talk. Quitting the description of his beloved equipment, he began to throw off his results, rather like a dog shaking itself after a bath. He had observed Jupiter and Saturn, measuring their positions with care, and he had found discrepancies from the Nautical Almanac. Running to the blackboard he wrote down the following figures, and then sat down:

  Discrepancy in Longitude

  Discrepancy in Declination

  Jupiter

  +1 minute 29 seconds

  –49 seconds

  Saturn

  +42 seconds

  –17 seconds

  Kingsley never heard the loud applause offered to Mr Green as a reward for his address, for Kingsley was choking with rage. He had come up to the meeting expecting to be told of discrepancies amounting to no more than a few tenths of a second at most. These he could have attributed to inaccurate, incompetent measurement. Or there might have been a subtle mistake of a statistical nature. But the figures that Mr Green had written up on the board were preposterous, fantastic, so large that a blind man could have seen them, so large that Mr George Green must have made some quite outrageous blunder.

  It must not be thought that Kingsley was an intellectual snob, that he objected to an amateur on principle. Less than two years previously he had listened in the very same room to a paper presented by an entirely unknown author. Kingsley had immediately perceived the quality and competence of the work and was the first person to give public praise to it. Incompetence was Kingsley’s béte noire, not incompetence performed in private but incompetence paraded in public. His irritation in this respect could be aroused in art and music as much as in science.

  On this occasion he was a seething cauldron of wrath. So many ideas flashed through his head that he was unable to decide on any one particular comment, it seemed such a pity to waste the others. Before he could reach a decision, Dr Oldroyd sprang a surprise:

  ‘I have great pleasure,’ said he, ‘in calling on the next speaker, the Astronomer Royal.’

  It had been the Astronomer Royal’s first intention to speak shortly and to the point. Now he was unable to resist the temptation to expatiate at length, just for the pleasure of watching Kingsley’s face. Nothing could have been calculated to torment Kingsley more than a repetition of Mr George Green’s performance, and this is just what the Astronomer Royal produced. He first showed slides of the equipment at the Royal Observatory, slides of observers operating the equipment, slides of the equipment taken to pieces; and he then went on to explain the detailed operation of the equipment in terms that might have been chosen for the benefit of a backward child. But all this he did in measured confident tones, unlike the rather hesitant manner of Mr Green. After some thirty-five minutes of this he began to feel that Kingsley might be in real medical danger, so he decided to cut the cackle.

  ‘Our results in broad outline confirm what Mr Green has already told you. Jupiter and Saturn are out of position and to amounts that are of the general order given by Mr Green. There are some small discrepancies between his results and ours but the main features are the same.

  ‘At the Royal Observatory we have also observed that the planets Uranus and Neptune are out of their positions, not it is true to the same extent as Jupiter and Saturn, but nevertheless in very appreciable amounts.

  ‘Finally I may add that I have received a letter from Grottwald in Heidelberg, in which he says that the Heidelberg Observatory has obtained results that accord closely with those of the Royal Observatory.’

  Whereon the Astronomer Royal returned to his seat. Dr Oldroyd immediately addressed the meeting:

  ‘Gentlemen, you have heard presented to you this afternoon results that I venture to suggest are of the very first importance. Today’s meeting may well become a landmark in the history of astronomy. It is not my wish to take up any more of your time as I expect you will have much to say. In particular I expect our theoreticians will have much to say. I should like to begin the discussion by asking Professor Kingsley whether he has any comment he would like to make.’

  ‘Not while the law of slander is still operative,’ whispered one professional to another.

  ‘Mr Chairman,’ began Kingsley, ‘while the two previous speakers were addressing us I had ample opportunity to perform a fairly lengthy calculation.’

  The two professionals grinned at each other, the Astronomer Royal grinned to himself.

  ‘The conclusion I have arrived at may be of interest to the meeting. I find that if the results that have been presented to us this afternoon are correct, I say if they are correct, then a hitherto unknown body must exist in the vicinity of the solar system. And the mass of this unknown body must be comparable with or even greater than the mass of Jupiter itself. While it must be granted implausible to suppose that the results given to us arise from mere observational errors, I say mere observational errors, it may also be thought implausible that a body of such large mass existing within the solar system, or on the periphery of the solar system, could so far have remained undetected.’

  Kingsley sat down. The professionals who understood the general trend of his argument, and what lay under it, felt that he had made his point.

  *

  Kingsley glowered at the railwayman who asked to see his ticket as he boarded the 8.56 p.m. train from Liverpool Street to Cambridge. The man fell back a pace or two, as well he might, for Kingsley’s rage had not been assuaged by the meal he had just eaten, a meal consisting of poor food badly cooked, condescendingly served in pretentious but slovenly conditions. Only its price had been ample. Kingsley stamped through the train looking for a compartment where he could bite the carpet in solitary splendour. Moving quickly through a first-class carriage he caught a glimpse of the back of a head that he thought he recognized. Slipping into the compartment, he dropped down by the Astronomer Royal.

  ‘First-class, nice and comfortable. Nothing like working for the government, eh?’

  ‘Quite wrong, Kingsley. I’m going up to Cambridge for a Trinity Feast.’

  Kingsley, still acutely conscious of the execrable dinner he had just consumed, pulled a wry face.

  ‘Always amazes me the way those Trinity beggars feed themselves,’ he said. ‘Feasts on
Mondays, Wednesdays, and Fridays, and four square meals on each of the other days of the week.’

  ‘Surely it’s not quite as bad as that. You seem quite put out today, Kingsley. In trouble of any sort?’

  Metaphorically the Astronomer Royal was hugging himself with delight.

  ‘Put out! Who wouldn’t be put out, I’d like to know. Come on, A.R.! What was the idea of that vaudeville stunt this afternoon?’

  ‘Everything that was said this afternoon was plain sober fact.’

  ‘Sober fact, my eye! It would have been much more sober if you’d got up on the table and done a clog dance. Planets a degree and a half out of position! Rubbish!’

  The Astronomer Royal lifted down his brief case from the rack and took out a large file of papers on which a veritable multitude of observations was entered.

  ‘Those are the facts,’ he said. ‘In the first fifty or so pages you’ll find the raw observations of all the planets, day-by-day figures over the last few months. In the second table you’ll find the observations reduced to heliocentric co-ordinates.’

  Kingsley studied the papers silently for the best part of an hour, until the train reached Bishop’s Stortford. Then he said:

  ‘You realize, A.R., that there isn’t the slightest chance of getting away with this hoax? There’s so much stuff here that I can easily tell whether it’s genuine. Can I borrow these tables for a couple of days?’