Fred Hoyle: The Black Cloud

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.”

“Is there anything wrong, do you think?”

“Nothing so far as I can see.” Marlowe took a magnifying glass out of his pocket and scanned carefully over the plate.

“Looks perfectly all right. No plate defects.”

“Tell me why you’re so surprised, Dr Marlowe.”

“Well, isn’t this what you wanted me to look at?’

“Not by itself. It’s the comparison with a second plate that I took a month later that looks so odd.”

“But this first one is singular enough,” said Marlowe. “You’ve had it lying in your drawer for a month! Pity you didn’t show it to me right away. But of course, you weren’t to know.”

“I don’t see why you’re so surprised by this one plate, though.”

“Well, look at this dark circular patch. It’s obviously a dark cloud obscuring the light from the stars that lie beyond it. Such globules are not uncommon in the Milky Way, but usually they’re tiny things. My God, look at this! It’s huge, it must be the best part of two and a half degrees across!”

“But, Dr Marlowe, there are lots of clouds bigger than this, especially in the region of Sagittarius.”

“If you look carefully at what seem like very big clouds, you’ll find them to be built up of lots of much smaller clouds. This thing you’ve got here seems, on the other hand, to be just one single spherical cloud. What really surprises me is how I could have missed anything as big as this.”

Marlowe looked again at the markings on the plate.

“It is true that it’s in the south, and we’re not so concerned with the winter sky. Even so, I don’t see how I could have missed it when I was working on the Trapezium in Orion. That was only three or four years ago and I wouldn’t have forgotten anything like this.”

Marlowe’s failure to identify the cloud — for this is undoubtedly what it was — came as a surprise to Jensen. Marlowe knew the sky and all the strange objects to be found in it as well as he knew the streets and avenues of Pasadena.

Marlowe went over to the sideboard to renew the drinks. When he came back, Jensen said:

“It was this second plate that puzzled me.”

Marlowe had not looked at it for ten seconds before he was back to the first plate. His experienced eye needed no ‘blinker’ to see that in the first plate the cloud was surrounded by a ring of stars that were either absent or nearly absent in the second plate. He continued to gaze thoughtfully at the two plates.

“There was nothing unusual about the way you took these pictures?”

“Not so far as I know.”

“They certainly look all right, but you can never be quite sure.”

Marlowe broke off abruptly and stood up. Now, as always when he was excited or agitated, he blew out enormous clouds of aniseed-scented tobacco smoke, a South African variety. Jensen marvelled that the bowl of his pipe did not burst into flames.

“Something crazy may have happened. The best thing we can do is to get another plate shot straight away. I wonder who is on the mountain tonight.”

“You mean Mount Wilson or Palomar?”

“Mount Wilson. Palomar’s too far.”

“Well, as far as I remember, one of the visiting astronomers is using the 100-inch. I think Harvey Smith is on the 60-inch.”

“Look, it would probably be best if I went up myself. Harvey won’t mind letting me have a few moments. I won’t be able to get the whole nebulosity of course, but I can get some of the star fields at the edge. Do you know the exact co-ordinates?”

“No. I phoned as soon as I’d tried the plates in the “blink”. I didn’t stop to measure them.”

“Well, never mind, we can do that on the way. But there’s no real need to keep you out of bed, Knut. Why don’t I drop you at your apartment? I’ll leave a note for Mary saying I won’t be back until sometime tomorrow.”

Jensen was excited when Marlowe dropped him at his lodging. Before he turned in that night he wrote letters home, one to his parents telling them very briefly of the unusual discovery, and another to Greta saying that he believed he’d stumbled on something important.

Marlowe drove to the Observatory offices. His first step was to get Mount Wilson on the phone and to talk to Harvey Smith. When he heard Smith’s soft southern accent, he said:

“This is Geoff Marlowe. Look, Harvey, something pretty queer has turned up, so queer that I’m wondering if you’d let me have the 60-inch for tonight. What is it? I don’t know what it is. That’s just what I want to find out. It’s to do with young Jensen’s work. Come down here at ten o’clock tomorrow and I’ll be able to tell you more about it. If you’re bored I’ll stand you a bottle of Scotch. That’s good enough for you? Fine! Tell the night assistant that I’ll be up at about one o’clock, will you?”

Marlowe next put through a call to Bill Barnett of Caltech.

“Bill, this is Geoff Marlowe ringing from the offices. I wanted to tell you that there’ll be a pretty important meeting here tomorrow morning at ten o’clock. I’d like you to come along and bring a few theoreticians along. They don’t need to be astronomers. Bring several bright boys … No, I can’t explain now. I’ll know more tomorrow. I’m going on the 60-inch tonight. But I’ll tell you what, if you think by lunch-time tomorrow that I’ve got you out on a wild-goose chase, I’ll stand you a crate of Scotch … Fine!”

He hummed with excitement as he hurried down to the basement where Jensen had been working earlier in the evening. He spent some three-quarters of an hour measuring Jensen’s plates. When at last he was satisfied that he would know exactly where to point the telescope, he went out, climbed into his car, and drove off towards Mount Wilson.