"Why do I need to learn this?" Gillian demanded. "The system recognises all the stars, when it can see them. And it can always find the pulsars. Why do I need to understand these coordinate systems?"
She was at a desk in the Navigation centre, with Mr Rogers. Her next simulation Walk was concerned with navigation. But she was bored by galactic coordinates and related navigation methods.
Mr Rogers replied, "Imagine you're using a GPS on any settled planet. If your gadget or the network fails, you'd have to go back to manual coordinates. You could even go back to a ruler, compass and maps if necessary - but you're still using a coordinate system."
"So you're saying I can use a ruler, compass and two-dimensional piece of paper for navigating around the galaxy?"
Now she was just being argumentative, and she knew it. She was tired, and the topic bored her.
Mr Rogers ignored her point. "Gillian, I'm afraid it comes down to legislative requirements. Ask Mr Dryen. To Walk this ship live, unsupervised, controlling the helm as a pilot, you must satisfy the Captain of your competence on this topic - and all the other designated ones. That means Abel must sign a legal document for each of the nominated competencies required of you as a Walker, and present them to the Captain. Galactic coordinates and their use is one of them. That's the law for the merchant navy."
Gillian sighed. "Ok, Ok ... Can we have a cuppa now?"
"Yes, good idea." Mr Rogers looked relieved. He glanced at her. "Didn't you sleep well last night?"
"I'm ok," Gillian replied, avoiding his gaze. She jumped up and marched over to the dispenser, trying to seem more energetic, adding over her shoulder, "Anyway, a compass is useless on a planet with no magnetic field - I know, I come from one!"
Mr Rogers put his head in his hands in mock desperation.
Mr Dryen, Dr Morris and Abel arrived.
"Is Gillian teasing you again, Mr Rogers?" Dr Morris asked. Now that she knew they were married, Gillian thought she detected an ironic tone in her use of the surname.
The group spent five minutes drinking tea and coffee, and exchanging small talk. Gillian loved these sessions. She was able to relax, as if she was a member of a large, happy family that sometimes had arguments, like all normal families.
"Well," Abel said, "time for our simulator session?"
Gillian stood and went over to one of the lockers to fetch a fresh mask. As she was leaving, she overheard Mr Rogers mutter to Dr Morris, "She's grouchy today!"
When she returned, Mr Rogers helped her up on to the stage. "Don't forget!" he said, "Imagine you're at the middle of a sphere, looking at its inside surface. The coordinates are on that inner surface."
They put her somewhere out between Sol and Tau Ceti, with her small green direction pointer turned off, and instructed her to look up the coordinates of Procyon and start Walking towards it. To do this, she had to flick her tongue to the roof of her mouth to bring up an inventory of all the stars within fifty light years. Then she scrolled to the required star by moving her eyes up and down to find it and its coordinates. Gillian had experienced difficulty accessing the actual maps on earlier attempts. It required her to focus on the list of star coordinates and blink twice at the one in the centre of her vision. Today, this seemed to have become easier, and she was please to see the map superimposed on her surroundings. She knew it was in three-D if she tried to perceive it the correct way, but so far, this ability eluded her.
Gillian felt relaxed, enjoying the surrounding starscape with no smelly clouds or weird semi-visible objects to distract her.
"Got the coordinates?" Abel asked.
Gillian read them off out loud.
"What major stars would you expect to see along the way?" Abel asked.
Gillian put a track on the map by blinking twice. "Sirius and Epsilon Eridani! You're not really going to make me Walk all that way are you?"
"We were considering it if you don't behave. But Mr Dryen's got another task for you."
"You've got the location of Procyon, now find the distance between it and Barnard's star."
"About fifteen light years?"
"You're guessing by looking at the map, but it's not bad. We'll make that homework. Let's move on."
"I've got a quick question," Gillian said.
"Ok, is it astrophysics, navigation or Walking?"
"Walking, I suppose."
"Then ask," Abel said.
"Ok, is there any danger of me getting confused between all these gestures? I mean selecting the wrong one and making the ship do something I don't intend?"
"No," Abel answered. "The system has all sorts of context-based checks against that problem. You'll notice the structure of the gestures is partitioned to prevent overlaps between function groups. All the helm operations are restricted to hand and foot movements."
They continued the navigation exercises for two more hours. Just before lunch, Abel glanced at Mr Dryen and Mr Rogers and announced, "Gillian, instead of debriefing and revision this afternoon, we want you to go live again. We've decided that you're advanced sufficiently ahead of our expectations for it to be allowed, and the Captain has agreed. We want you to Walk about fifteen light years towards the little globular cluster that's between the bubble and us. Are you ok with that?"
Gillian was excited. "Wow! Is there something urgent for you to want to push on?"
Mr Rogers replied, "Our entire trip is urgent. But the globular cluster up ahead is so strange that we should take a closer look at it as soon as possible."
Mr Dryen added, "Travelling a little further today suits the Captain because he's facing pressure from some of the passengers, obviously the ones with the valuable cargo. And the Executive Officer's survey of passenger morale showed a significant peak after you Walked a few light years during our last session. So we'd like to keep the good news flowing."
"We need to be careful with these rare earth miners and traders," Abel remarked. "I doubt they know we plan to set the ship down out beyond Jupiter's orbit."
Dryen replied, "I suspect they do, but they're prepared to worry about that when we get closer to the final approach. We may come under some pressure then."
Abel said, "It doesn't matter how much pressure they choose to create. I seem to have wrecked the parts of my brain that let me Walk."
Gillian said, "What are we doing for lunch? I'm starving."
They took her to a café in the meadows not far away. Gillian wolfed down beef stroganoff with noodles followed by yoghurt and fruit, then had two coffees and a small ice-cream.
"You'd better relax, and let your tummy settle after all that food," Dr Morris remarked.
"I'm ok."
Abel said, "I agree with Dr Morris."
Gillian generally obeyed Abel, so that settled it. She leant back in her seat and gazed out at the meadows, a view she now found pleasant and calming, having now grown accustomed to its vast, open space. It was full of people relaxing, enjoying themselves, some playing games, others picnicking together, or lying around chatting. Little groups were everywhere, around the café and the Navigation Centre, up the sloping ground on either side of them and far away above her head: all around the rim. Gillian was seized with the realisation of their dependency on her. But she wasn't worried. She experienced a thrill tinged with nervousness that she was again about to take the ship's helm. Otherwise, she was relaxed, confident in her abilities.
Her mind grew tranquil.
"Gillian?"
She jerked in her seat, startled. Joan Rubilio filled her vision, bending towards her with a concerned face. "Are you ok, Gillian? Where did you go?"
"What? - I'm fine!"
"You don't sound sure of it."
"I just drifted off, relaxing."
"You were gazing straight at us, silently, with a strange blind gaze. It was unnerving. Where did you go to?"
Gillian looked at all the other concerned faces staring at her. "I suppose I went into a kind of meditative state." She was embarrassed. "Was I really odd looking?"
"Yes," Dr Morris said.
"Well, I felt relaxed, and... contented. I drifted!"
"Ok."
Gillian wanted to forget the episode and rejoin the conversation. Choosing her moment a few minutes later, she remarked, "I found smutty drawings of me on the ship's network. Someone's invented new navigational gestures for me to make ... with surprising parts of my body."
"Oh, no!" Dr Morris sighed. "I hope it didn't upset you too much."
"It gave me a shock at first, some of it's pretty bad, but other stuff made me giggle. It's obviously thirteen year-old boys; you know how horrible they can be. I saw one of me bending over, it's called 'moon rise over' -"
"It's time to head back," Abel said.
In the Navigation Centre, they found Captain Xing waiting for them. After a polite greeting, Gillian hopped up on to the stage, almost feeling at home there, and slid her mask on. She clasped her hands together and plunged into the clouds and stars of what people were now calling "Outside the Bubble". Once more, the green coordinates and direction arrow appeared before her. But now she also had the small blinking red light that indicated she was live, in command of the ship's helm.
"Have you set up the course to the cluster already, Mr Dryen?" Gillian asked.
"Yes, it's done."
Gillian commenced Walking in the same manner as in her earlier session, following the green arrow, stepping between the clumps that indicated high gas densities, avoiding or sliding between the macro-quantum objects. She continued like this for an hour, enjoying the feeling of being in control of the ship. Then she noticed that the spacing between the cloud clumps was increasing.
"Have you seen this, Abel? The clouds seem to be thinning out!"
"Yes, I can see you're going faster, too. We're making good progress!"
With the volume of clouds decreasing, the growing cloud gaps allowed Gillian to walk around the clouds more often instead of expending effort to step over them.
"Do we understand why they're thinning?" Gillian asked.
"No - I don't. Mr Rogers?"
"We believe they 'condensed' in the first place from turbulence, if you can call it that in a near vacuum. Turbulence occurs downstream of obstacles. It can be a denser region of the gas itself, or a large object. I think the turbulence must be caused by the globular cluster we're heading towards. You've begun to walk out of the direct downstream area, Gillian, so the gaps are widening."
"I see. Is it ok to speed up more?" Gillian asked.
She heard Mr Dryen talking in the background, and Abel assenting.
"No. You're going fast enough. Don't lengthen your steps. Just go carefully as you are, relax."
"Ok."
"We've never seen these regular cloud structures before," Abel remarked. "It's not like Walking in the bubble. You're exploring something new, Gillian."
Gillian marched on, and the clouds continued to thin. Now that she was making uninterrupted progress, she noticed how often she needed to shrug her shoulders to turn around on the stage. It intruded on the reality of her walk, and was at once mildly irritating and reassuring. She wasn't really out here, unprotected and alone in deadly interstellar space. She was safe inside the ship, tramping up and down on a raised platform, possibly looking a little silly.
The counter on her display had gone down five light years.
She continued Walking. The brown clumps of cloud now thinned out so much that she only needed to take avoiding action every five or ten minutes.
"Eight light years, Gillian," Abel said. "You're making good time!"
"Thanks!" Gillian replied. "I've been watching my distance to the edge of the bubble counting down. Sorry, I mean our distance - the ship's."
"Don't get too focussed on watching that counter; you might miss something important."
"I'm being careful, I promise."
She noticed that she could even see more stars.
Some minutes later, Gillian said, "Abel, there's a very bright, tiny group of stars up ahead, compared with what else is around here, anyway. Is that the globular cluster?"
"Yes, about seven light years away," Abel replied.
"Ok. It looks interesting now; I wonder how spectacular it'll be when we get closer. Will we explore it?"
"No, we won't be travelling into it. We don't have time for the detailed external surveys necessary for risk assessment. That will be the job of another expedition, one day. The Captain's authorised Mr Dryen to give you a course correction soon, so that we arrive at a suitable observation distance just outside the cluster."
Disappointed that there was no plan to explore the strange system, Gillian Walked on for another five light years, and watched the cluster grow brighter, and more spectacular. It looked like a brooch made of tiny, brilliant diamonds.
She heard Mr Dryen talking quietly to Abel again. Abel called out new target coordinates, and added, "It's easier for you just to turn left one tenth of a degree. You'll need to expand your direction scale to do that. Or we can tweak it for you if you like."
"No. Let me do it for the practice. Er, what gesture is it? I've forgotten."
"It's one of the more obscure ones," Abel said. "You put the palms of your hands on your cheek and slide them both back."
Gillian followed his instructions and the green scale in her vision expanded until it was only five degrees wide, with tenths, halves and quarters marked off.
With the bigger scale, Gillian was able to accurately turn to her left one tenth of a degree, allowing the direction arrow to drift the same amount to the right, because its scale had expanded too. Her distance from the cluster was still so immense that to her eyes the course seemed unchanged. She continued Walking.
"Shall I bring the coordinates scale back to the usual, Abel?"
"If you want to."
Gillian put her hands on her cheek and brushed them forward.
As she Walked on, the cluster slowly grew brighter and larger, and moved a little to her right. She could now almost count the stars packed inside it.
"We've had our instruments focussed on the cluster for a while," Mr Rogers said. "We can see about thirty G-type stars packed into it, in a space of under two cubic light years. That's very strange!"
"Shall I keep Walking?" Gillian asked.
There was a short silence. The Captain and the rest of the group conversed in soft voices before Mr Rogers answered.
"Yes, continue. We'll tell you when to stop."
One quarter of a light year out, Mr Dryen ordered Gillian to halt.
She took off her mask and turned to step off the stage, but halted in surprise. Thirty or more people had crowded into the Navigation Centre. Mr Dryen came forward, without his cane, and helped her step down, his face excited.
"What's happened?" Gillian asked.
"That globular cluster you've brought us to," Mr Dryen said. "It's artificial, and it's full of enormous space habitats."
"Wow! An alien civilisation?"
"Yes."
"Are we going to contact them?"
"Oh, there's no sign of life there. They're probably all long dead, or long gone."
"Like the other remains we've found all over the bubble?"
"That's right. The cluster is a ruin. There's no sign of life, across the entire electromagnetic spectrum."
Mr Dryen showed her images from the telescopes. Most of the habitats, gigantic cylinders dozens of kilometres long, were tumbling and had drifted out of their orbits. Others had broken up. One appeared crumpled and bent, with an enormous jagged hole where something large had struck it.
"A missile? A war?" Gillian asked.
"We don't think so. Just the inevitable meteor strike, ages after the civilisation itself vanished. The whole structure seems to be twenty or thirty million years old!"
"We should go in there and explore!"
Mr Dryen shook his head. "The Captain wants to push on. You know the pressure he's under. We'll record all we can, and that's plenty. Someone will be back here one day."
Mr Rogers joined them. "This is amazing! We've found plenty of extinct alien civilisations before, but nothing like this. The stars in that cluster can't have formed so close together naturally. They were moved! Every one of them is a main sequence G-type, like the Earth's sun. This was a stupendous civilisation." Mr Rogers shook his head. "It's incomprehensible."
"There must be amazing things in there!" Gillian exclaimed.
"Well, one particularly amazing thing: those stars are still in stable orbits! They haven't wandered away - something's still holding them in place. We're trying to find what it is."
"But the whole civilisation is dead," Gillian said. "It's so sad!"
"It's not so very sad," Abel said. "Just normal. They had their time, and probably a very long one, much longer than the human race has existed."
A strange burst of anger surprised Gillian. But all she said was, "We never, ever, find any live, functioning alien civilisations. I think that's even sadder!"
Abel spread his hands. "The galaxy's vast, and it's ancient. Random super-nova blasts eventually destroy all civilisations, usually with gamma ray bursts. That's why we're unlikely, ever, to run across a live alien civilisation. They're either too far away, too far in our past, or too far in our future."
Something within Gillian made her wonder at this confident assertion.
"And of course, one day a super-nova blast will get us too!"
Later, after the marines had escorted her back to her cabin, Gillian lay on her bed, thinking of the brilliant, ruined star cluster she had seen. She imagined far away, wonderful civilisations, and the exquisite artefacts and incredible, wonderful knowledge that was always to be carelessly annihilated by the blind, hiccupping plumbing of unstable stars. It wasn't even evil. It was random, infinite carelessness. That made it worse. The universe doesn't care a damn about you, she told herself.
But her steady, logical inner mind was unperturbed.
Later, when the twilight had been turned on, she rose, put on her jacket and hood, and stole away into the darkness.