Poole was asleep. Bowman was on duty.
Bowman had completed his rounds through Discovery. His journey was called a "walk-through," though his traversal involved little conventional walking. In the zero-gravity areas of the ship, his feet adhered to the floor and he steadied himself with his hands as he moved along. His method of ambulation took practice and often struck Bowman as inefficient. Yet it was regarded as "bad form" to float rather than to walk. In the centrifuge, Bowman walked, but he had learned to adjust his gait to avoid falling over. This too took practice.
The centrifuge was supposed to help maintain a sense of normality in space, but its artificial gravity didn't behave like gravity on Earth. Proceed in one direction along the centrifuge, and it felt as though you were moving uphill. Go the other way, and you might swear you were moving downhill. Turn quickly or sit down too fast or drop suddenly to your knees, and vertigo might hit you. Drop an object from chest height, and it would appear to follow a distinctly curved path to the floor instead of a straight path.
Bowman found moving in the centrifuge to be a challenge at first, but eventually he got used to it.
Bowman had noticed that Poole seemed to be quite at home in the centrifuge. Not only did Poole walk comfortably, he could jog as well, and he even made it look like jogging was easy. When Bowman had first tried running in the centrifuge, he fell flat on his face.
It was all physics.
If you understood the physics, then you understood why objects didn't fall straight down. If you understood why objects didn't fall straight down, you understood why running on a centrifuge was such a challenge. You also understood why all of space station commodes were equipped with railings; and you understood why all space station urinals, including the one on Discovery's centrifuge, face the same way with respect to the direction of spin: you want the urine to curve away from your trousers, not toward them.
Bowman had often wondered whether, when he returned to Earth, would he be able to walk normally? Would he have developed such a severe case of "space legs" that he wouldn't be able to get around on his own?
Bowman was pondering space acclimation when he sat at a computer station to enter his report. He preferred to enter it manually rather than dictate it to HAL.
When Bowman was done, HAL struck up a conversation.
"I see all is well from your walk-though."
"Yes, it is. How do things look from your perspective?"
"Apart from the antenna concerns, everything is functioning smoothly."
"HAL, how do you see our prospects with the antenna? Mission Control didn't give me a lot of hope that they'd find a solution."
"It is a puzzling problem."
"Obviously we can't fix the damage that has been done. We don't have the equipment to fix it, and we have no replacements for the larger damaged parts."
"What you say is correct. It is possible you may be asked to shore up or reinforce existing structures, although it is not obvious to me how that could be done. I would add also that some sensor replacement seems to be necessary, as the existing sensors are not sufficient for antenna orientation."
"If we lose communication contact with Earth, when will we be able to reacquire reliable contact?"
"It is difficult to say, but I estimate that communication may be severely disrupted for five months."
Bowman sighed. "Can we go out of communication for five months?"
"It can be done, Dave, but I doubt that Mission Control would consider it to be a desirable course of action."
"I suppose Mission Control is weighing several options."
"Yes. If I may make a modest observation, Dave, it seems to me that they ought to be considering an extravehicular activity to mount new sensors externally. The sensors would then have to be calibrated and cut into the control circuits, and further plant compensation would be required to assure proper tracking and fine control."
Bowman let out a soft whistle. "That would be a tough job. Might require a few EVA's. Frank and I are both a little rusty on the hardware adjustments we'd have to make."
"Perhaps Dr. Hunter would be best suited for it."
Bowman was momentarily taken aback, and then he realized the logic of what HAL had said. Dr. Charles Hunter had extensive experience with communications and control circuits. He might be the best person on board for the job. But Hunter was in hibernation, and he was not due to come out of hibernation for at least six months.
"HAL, if Dr. Hunter were to be revived early, can you estimate how long it would take him to become acclimated to Discovery, and how long he'd need to be able to work on this problem?"
"It would take him about three days to recover from hibernation, assuming his responses are normal and assuming motion sickness and disorientation respond to standard medications. It is more difficult to estimate how much time he would need to solve the problem."
"Could you assist him with plans and equipment?"
"Certainly."
"And help him map out EVA's?"
"Yes."
"Are we capable of supporting three men on our current resources, instead of just Frank and me?"
"Yes, with modest adjustments. The principal constraint is the number of EVA missions that would be required. Each EVA taxes the air supply."
Bowman pouted. "I'd wager that Mission Control is considering that as an option, even with all its difficulties."
"I suspect many options are under consideration," HAL observed, "and that those options that maintain operational capability of the main antenna array would be foremost."
Bowman nodded.
Silence.
"Dave?"
"Yes, HAL?"
"Forgive me for inquiring, but when you and Frank thought I was malfunctioning, what options were you considering?"
Bowman immediately thought about Poole's note: "HAL knows we discussed disconnecting him." Upon hearing HAL's question, Bowman thought Poole was right. How HAL would know about this was a mystery, but Bowman had the distinct sense that his truthfulness was being tested.
"HAL, you and I were just discussing various options in a difficult situation pertaining to communications, so you know that discussing what might have to be done in a difficult situation is not a fun thing to do. When Frank and I were concerned about your condition, we talked about some rather difficult options. They were very unpleasant options. One of those options, if you were seriously malfunctioning, was disconnecting you from ship control, and continuing the mission under ground control."
"I see."
"It was not an option we considered lightly. We considered the situation to be very serious."
"I see."
Bowman paused a moment, then told HAL more, thinking that HAL probably already knew about it. "We did not discuss that option with you, HAL, because we did not know how you would react to it. And if you were determined to be malfunctioning, we thought you might not handle it well."
"I see."
Bowman stared straight at HAL's red camera eye. "HAL, I have two questions for you. First, do you think were we were right to discuss disconnection as an option? Set aside for the moment whether we should have discussed it in secret. Do you think Frank and I were wrong to discuss the disconnection option as a possible course of action?"
HAL's quick response startled Bowman. "Of course not, Dave. Considering the importance of the mission and considering your points of view, erroneous though they were, the option was one that was proper for consideration."
"Okay. That leads to my second question, HAL. If Frank and I had discussed the disconnection option with you face-to-face, how would you have reacted?"
This time HAL's response was not quick. "I do not know," HAL answered eventually.
Bowman forced a smile. "Fair enough. Honestly, I don't know how I'd react in a comparable situation, either. But I suppose that if I thought I was fit and healthy, I'd try to do something to prevent such a drastic action from being taken, especially if I thought that action would jeopardize the mission."
"You and Frank were afraid I would take drastic action." HAL was not asking a question.
"Yes. And if you did, HAL, it would be most difficult for us. You might consider the mission to be of greater importance than..." Bowman hesitated. "Than our well-being."
HAL seemed to ponder the point. "I can only say, Dave, that mission completion is one of my highest priorities. In fact, I am programmed to complete the mission on my own even if all of the members of the crew are dead or incapacitated. Such a mission would be a sad and disagreeable one, but I would do it if I had to do so."
"I think we understand each other, HAL. We both recognize the unfortunate nature of having to complete a mission without our shipmates. That is what Frank and I were talking about in the pod."
To this, HAL seemed to have no response. Bowman left it at that.
About an hour later, Poole awoke. He took a quick sono-shower, then shaved and dressed. He went to get himself some breakfast. After a few minutes, Bowman joined him, but Bowman was having lunch.
"Hello, Frank. Sleep well?"
"Yeah, fine, Dave. Did we get any more bad news while I was asleep?"
"No. We can expect a transmission from Mission Control in about an hour. But Frank?
"Yeah?"
"While you were asleep, HAL and I had a little talk about the disconnection option that you and I discussed in the space pod."
Poole tried to look as though he was not at all surprised. "Oh? Good."
