Actually, outside the ship there was nothing even faintly corresponding to the look of things from within. The small vessel of space actually floated in nothingness. Its hull glittered with that total reflection coating which was so nearly a non-radiating surface and was therefore so effective in conserving the heat supply of the ship. There was a glaring yellow star before the ship's nose. There were other white-hot stars off to port and starboard. There were blue and pink and greenish flecks of light elsewhere, and all the universe was specked with uncountable suns of every conceivable shade. Askew against the firmament, the Milky Way seemed to meander across a strictly spherical sky. From outside the Med Ship, its nature was self-evident. Everywhere, suns shone steadily, becoming more and more remote until they were no longer resolvable into stars but were only luminosity. That luminosity was many times brighter where the Milky Way shone. It was the Milky Way.
Minutes went by. The Aesclipus Twenty continued to float in emptiness. Then, after a certain interval, the outside airlock door swung open again and remained that way. Then a radiated signal spread again through the vacancy all about. It had begun before, when the outer door was opened, and cut off when it shut. Now it began to fill a vast spherical space with a message. It traveled, of course, no faster than the speed of light, but in one minute its outermost parts were eleven million miles away. In an hour, they would fill a globe two light-hours in diameter—sixty times as big. In four or five hours, it should be detectable on the planets of that nearby yellow star.
Calhoun regarded the light on the ship's control-board which said that a signal was being transmitted. He hadn't sent it. He hadn't ordered it. The ship had sent it off itself, as of itself, it had tried to lure him out to the vacuum beyond the air-lock.
But the ship was not alive. It could not plan anything. It could not want anything. It had been given orders to lie to him, and the lies should have caused his death. But a man would have had to invent the lies. Calhoun could even estimate exactly how the orders had been given—but not by whom—and where they'd been stored until this instant and how they'd been brought into action. He had no idea why.
The Med Ship was inevitably a highly complex assemblage of devices. It was impractical for one man to monitor all of them, so that task was given to another device to carry out. It was the control-central unit, in substance a specialized computer to which innumerable reports were routed, and from which routine orders issued.
Calhoun did not need, for example, to read off the CO2 content in the ship's air, the rate of air-renewal, the ionization constant, the barometric pressure and the humidity and temperature to know that the air of the ship was right. The control-central unit issued orders to keep it right, and informed him when it was, and would order a warning if it went wrong. Then he could check the different instruments and find out what was the trouble. However, the control-central made no decisions. It only observed and gave routine orders. The orders that were routine could be changed.
Somebody had changed them; very probably a new and extra control-central unit had been plugged into the ship and the original one cut off. The extra one had orders that when the ship came out of overdrive it was to present pictures of Med Service Headquarters and report other data to match. It could not question these orders. It was only a machine, and it would carry them out blindly and without evaluation.
So now Calhoun ought to be floating in emptiness, his body an unrecognizable object whose outer surface had exploded and whose inner parts were ice. The ship had carried out its orders. Now, undoubtedly, there was something scheduled to happen next. Calhoun hadn't started the signal. It would not be transmitted—it would not have been planned—unless there would be something listening for it, another ship, almost certainly.
Another item. This had been most painstakingly contrived. There must be orders to take effect if the first part did not dispose of Calhoun. The ship had been a deadfall trap, which he'd evaded. It might now be a booby trap, just in case the deadfall failed to work. Yes. A man who orders a machine to commit murder will have given it other orders in case its first attempt fails. If Calhoun went down to verify his suspicion of an extra control-central, that might be the trigger that would blast the whole ship; that in any event would try to kill him again.
Murgatroyd said, "Chee! Chee!" The vision screens meant to him that there must be people waiting outside to give him sweet cakes and coffee. He began to be impatient. He added in a fretful tone, "Chee!"
"I don't like it either, Murgatroyd," said Calhoun wryly. "Somebody's tried to kill us—at any rate me—and he must think he had some reason, but I can't guess what it is! I can't even guess how anybody could get to a Med Ship at headquarters to gimmick it if they wanted to slaughter innocent people like you and me! Somebody must have done it!"
"Chee! Chee!" said Murgatroyd, urgently.
"You may have a point there," said Calhoun slowly. "We, or at least I, should be dead. We are expected to be dead. There may be arrangements to make certain we don't disappoint somebody. Maybe we'd better play dead and find out. It's probably wiser than trying to find out and getting killed."
A man who has detected one booby trap or deadfall designed for him is likely to suspect more. Calhoun was inclined to go over his ship with a fine-toothed comb and look for them. A setter of booby traps would be likely to anticipate exactly that and prepare for it. Lethally.
Calhoun looked at the pilot's chair. It might not be wise to sit there. Anybody who received the ship's self-sent call would receive with it an image of that chair and whoever sat in it. To play dead, he shouldn't do anything a dead man couldn't do. So he shrugged. He sat down on the floor.
Murgatroyd looked at him in surprise. The signal going-out light burned steadily. That signal now filled a sphere two hundred million miles across. If there was a ship waiting to pick it up—and there'd be no reason for the call otherwise—it might be one or two or ten light-hours away. Nobody could tell within light-hours where a ship would break out of overdrive after three weeks in it.
Calhoun began to rack his brains. He couldn't guess the purpose of his intended murder, but he didn't mean to underestimate the man who intended it.
Murgatroyd went to sleep, curled up against Calhoun's body. There were the random noises a ship tape makes for human need. Absolute silence is unendurable. So there were small sounds released in the ship. Little, meaningless noises. Faint traffic. Faint conversation. Very faint music. Rain, and wind, and thunder as heard from a snug, tight house. It had no significance, so one did not listen to it, but its absence would have been unendurable.
The air apparatus came on and hummed busily, and presently shut off. The separate astrogation unit seemed to cough, somewhere. It was keeping track of the position of the ship, adding all accelerations and their durations—even in overdrive—ending with amazingly exact data on where the ship might be.
Presently Murgatroyd took a deep breath and woke up. He regarded Calhoun with a sort of jocular interest. For Calhoun to sit on the floor was unusual. Murgatroyd realized it.
It was at just this moment, but it was hours after breakout, that the space communicator speaker said metallically, "Calling ship in distress! Calling ship in distress! What's the trouble?"
This was not a normal reply to any normal call. A ship answering any call whatever should identify the caller and itself. This wasn't normal. Calhoun did not stir from where he sat on the floor. From there, he wouldn't be visible to whoever saw a picture of the pilot's chair. The call came again.