For a few moments no one was bothering him and he could be alone. Sleep was out of the question. There would be plenty of time for that later if they avoided the present trouble. Even while he was thinking about this, his feet were making up his mind for him. Without consciously coming to a decision, he was out in the corridor and heading for the nearby elevator. The observatory, of course, that was where he wanted to go.
While the elevator crawled up its shaft he called the duty man in the control-room and reported where he would be.
The elevator went up from the outer skin, really inwards to the midpipe that connected the two sections of the spacecraft. When the elevator stopped and the door slid open, Don grabbed the edges and pulled himself forward. With gentle ease he floated out, hanging suspended in mid-air. As soon as he touched the far side of the padded midpipe he grabbed one of the flexible handles located there and pulled himself towards the observatory.
Since the spaceship, with its engines turned off, was in free fall, there was no feeling of weight or gravity at all. The rotation of the ship created centrifugal force in the outer deck areas. But here, at the centre of rotation, the forces were cancelled out and he could float as easily as a fish in water. The observatory door opened when he touched the button and he drifted on through.
As always, the breath caught in his throat at the incredible sight. Stars, rivers of stars, galaxies of them turning slowly before his eyes.
The observatory was a great transparent bowl at the end of the midpipe, where it projected from the drum. Here, without any air in the way to diffract and dim them, the stars did not twinkle. They were hot points of light, of different colours and varying brightness, filling the bowl of darkness overhead. It was easy to forget the transparent covering and feel the sensation of being with them, among them, a part of the infinity of the universe.
There was the sun, off to one side, its glare automatically dimmed by the material of the dome. It reminded Don of the storm, already brewing on that fiery surface, and he checked the radiation counter. It was up slightly, but not enough to cause damage. Going up steadily, that's what Holtz had said. How much time did they have before that storm of destroying particles hit? And what could he possibly do to save the lives of all the people in his care? He pressed his clenched fists to the cool surface of the dome.
If there was a time for despair, this was it, when he was alone and unseen. He was tired, almost exhausted, and part of him wanted to give up on the spot. Pass the buck to someone else. There in the darkness, he smiled at the thought. There was no one else: this was where the buck stopped. As a doctor he had been trained to accept responsibility for life and death. He had never thought when he took his Hippocratic oath that it would include being captain of a spaceship. He hadn't learned much about that in medical school! He smiled again at this thought and felt better. He would keep doing the job, to the best of his ability. That was the only course open to him.
The phone buzzed, loud in the silence of the galaxy-embracing chamber. He picked it up.
'Captain here,' he said, automatically now that the decision had been made.
'Control-room, sir. The tapes of the message from Mars Central have been processed by the computer. I have a transcription here of the complete message - do you want to hear it?'
'Just the figures. How strong is the storm going to be - and when does it hit us?'
'Just a moment... here it is. Force eight on the Hoyle scale. Ten is the tops, and I've never seen one over six before 'So it's strong. I get the message. Now, when is it due?'
'One and a half hours at the soonest. May be delayed a few minutes past that, but no more.'
Don silently expelled the breath that he had, unknowingly, been holding. 'All right. I'm on my way to control. Contact a passenger named Ugalde and have him meet me there soonest. And Chief Kurikka as well.'
Ninety minutes to turn the ship. It didn't seem possible. But it had to be done. Concentrating fiercely, Don found his way automatically back to the control-room, to face a furious Doctor Ugalde.
'The impossible you ask of me, Captain, and then to do it immediately. And then you interrupt! Such things cannot be...'
'Less than an hour and a half until the storm arrives,' Don said quietly. 'Our time has run out, Doctor.'
Ugalde's face went grey and he half-dropped into the chair next to him. 'Then... it is all too late,' he whispered.
'I don't think so. We are just going to have to make the manoeuvres by the seat of our pants.' Don had to smile when he saw the shocked expressions on the faces of Kurikka and the duty man. 'We have no other choice - and I wish you wouldn't look so astonished. You all know that commercial jetliners are almost completely controlled by automatic devices. Yet I'll bet you have all flown your own lightplanes or copters yourself. Spacers are no different. The first astronauts had to fly by wire when the automatics went out. We'll do the same. Kurikka, just what is involved in an attitude change, to move the axis of rotation?'
The Chief looked gloomier than ever. 'It's all done by the computer, sir. The astrogator feeds in the data and instructions, then we just sit back and watch it happen.'
'Isn't there a provision for manual control, in case something should go wrong?'
'There is, though we have never had to use it. Those controls there.'
Don went over to the indicated board and looked at the dials and switches. 'Now can you - simply - tell me what happens when an attitude change is made?'
None of this was by the book, and Chief Kurikka lived by the book. Yet he was intelligent enough to know that there were times when the book had to be thrown away. Reluctantly, in spite of himself, he came to the control board and switched on the screens.
'There are two television pickups,' he said. 'One in the bow, in the observatory, and the other in the stern. It's on the centre line between the main drive rockets. This is the bow picture.'
He pointed to the screen with the sun appearing off to one side, the same scene that Don had watched from the observatory. Kurikka continued.
'There is a track around the reactor sphere, just at the base of the main tubes. A small reaction rocket rides this track, moving in the direction opposite to our spin. This cancels out the spin so that the rocket always faces the same direction. A short burst is fired, just enough to start the ship tumbling, end over end. The ship turns until it is orientated in the new direction - then the computer fires the rocket again cancelling out the motion.'
Don looked at his watch, then forced himself to look away without seeing how little time was left. There was a simple answer here. Almost too simple, he realized. He turned and motioned to the Mexican mathematician.
'Dr Ugalde - would you come here please and check me out. You've heard what the Chief said, so you know our problem. The sun is now before our bow, just about 180 degrees wrong. Now, if the rocket were fired the ship would turn end for end in space. When the sun appeared in the middle of this stern screen we would be facing in the right direction, with the reactor between us and the solar storm. At that time the jet will be facing in the opposite direction, and if it were fired the rotation would stop and our attitude would be correct. Will that work?'
Ugalde frowned in concentration, then scribbled some brief equations in his leather-bound notepad.
'It won't work that easily,' he said. 'The second rocket blast must be exactly as long as the first, and must be timed so that it ends with the ship on the correct orientation...'