Earth Orbit

For a moment, as Liam lay in shock, Gillian held her breath. But the instrument echoes she saw from his mask showed that everything was normal.

"Don't worry, we're Ok!" Mr Dryen announced. "The system caught it!"

The ship was safe. As Liam sat up on the stage, Gillian pulled her mask off. Even still wearing his mask, Liam looked dejected. He pulled it off slowly and looked up at Gillian.

"I did it again!" he muttered.

Gillian walked over and gave him her hand. He stood up, towering over her, and looked so downcast that she wanted to put her arms around him and take his head on her shoulder. But Liam was too tall for that.

"Don't worry, Liam," Gillian said. "This is just something you'll have to get past. You'll grow out of it, I'm sure." She looked up at his face. "And you've just piloted this ship back to the home system!"

"There is that, I suppose," he muttered, glancing around the Navigation centre, where people were going about their business or, if they were guests, starting to leave. Captain Xing gazed at him and saluted. "Well done, Mr Pendry!"

"Thankyou, Captain!" Liam replied.

They stepped off the stage together, and Celia joined them. She gave Liam a demure kiss. "Congratulations, Liam - your first live Walk! Bad luck about the fall."

"Thanks, Celia. I could have done without such an embarrassing finish!"

"Pendry," Gillian said. "Liam 'Pendry'. We don't get to hear surnames much, except from the Captain. I'm 'Mr Berry', by the way."

"He calls you 'Mr'?"

"I think it's supposed to be an honorific. It's a merchant navy custom, I presume."

Celia said to Liam, "I saw you turn towards Gillian just before you fell; it looked like you were saying something. That must have distracted you."

Liam nodded, his face downcast. "I should keep focus right up until I go offline." He turned to Gillian. "So it looks like you're on for the final leg?"

"Apparently," Gillian replied. "I don't know when. The let-down needs some planning. We have to map a route through the Oort cloud, before we can work out a let-down path into the ecliptic plane." She added, "And they've added a special control to disconnect me if I, um - have another turn."    

This work began immediately. Mr Morris and Mr Dryen, having pin-pointed the exact location of the ship relative to the sun, now plotted its position relative to the latest Oort cloud maps, and their latest observations.

"The outer comets and planetoids in the Oort cloud are constantly perturbed by nearby stars, so they tend to wander," Mr Morris told them. "That's why everything has to be recalculated for each let-down. Right now, we think we've got a clear path to a spot in the solar system about twenty degrees above the ecliptic plane, with only a couple of course changes."

He explained that the Oort cloud was rocky junk, ice and other frozen gases, with planetoids and two full-size planets as large as the Earth. It all rotated around the solar system up to a light year out. Automated observatories, permanently positioned in the cloud, tracked all the major and some minor bodies, and calculations located the rest, using the gravitational effect of the major masses. The map needed to be updated on each return journey.

Mr Morris rotated the three-dimensional version of his map in front of them, to highlight Gillian's proposed path.

"I'd say it'll be about an hour, maybe a bit under, for you to cross through the cloud, Gillian," Mr Dryen said. "You'll see we've marked the end of the let-down on the orbit of Earth at L5. We'll treat that as the notional target; nobody expects you to get exactly there."

Abel added, "Just do the best you can manage, Gillian. Go as close to the Earth's orbit as you think you can with safety. Make sure your errors lean towards the orbit of Mars, not Venus. We don't want you to trip and fall into the sun."

"So, no pressure then?" Gillian said, with a nervous smile.

Gillian's Walk was to commence the next day. That evening, she, Celia and Liam strolled together in the rim park. A few paces behind, two marines followed them.

"It's so nice to be back here!" Gillian sighed.

"It's a pity the Captain won't allow your parents to join you," Celia said.

"I suppose I can't complain much," Gillian replied. "He's got good reasons to be cautious with us."

"What does he think your parents and you might do?" Liam asked.

"He doesn't know," Gillian answered. "And neither do we. That's the problem."

"So it's the precautionary principle?" Celia asked.

Gillian glanced at her, noticing that she and Liam were holding hands. Behind them, she guessed that her two marines were listening.

"I suppose it is, Celia. But it's hard to be separated from Mum and Dad just when they came back from their, er, long sleep. We've so much to talk about."

The next day, Gillian commenced her Walk. She put on her 'pointe' ballet shoes, ready for finely judged steps towards the end of the Walk. The plan for her journey, made for her by Mr Dryen and Mr Morris, and reviewed by Abel, was to be visible on her mask display at her choice. If Gillian glanced down, the Oort cloud navigation map appeared in her vision, projected on top of the green direction arrow. Additional prompts would appear on her mask display to notify her of upcoming turn points.

The Navigation centre seemed even more crowded than usual that day. Gillian knew that this was because of her notoriety. Despite whatever cover stories the Captain's team had put about, rumours of her "hijack" of the ship were now widespread.

Gillian took one last look at her swollen audience, nodded at Captain Xing, and smiled at Mr Dryen, Mr Morris and Abel. She waved at Celia and Liam, and then stepped up on to the stage, pulled her mask over her head, and just as Mr Dryen muttered, "Go!" she clasped her hands together.

She was on the edge of the Oort cloud, but she only knew this from her map and instrument readings; what she saw was the same view as yesterday. Despite the Oort cloud being a cluttered, potentially dangerous environment for starships, from a human perspective it still looked as empty as interstellar space. There was no visible evidence of its existence in front of her. She saw only the orange-yellow star that was her destination.

Gillian turned to follow the green arrow towards her first turn point. She had about a light year to go through the Oort cloud, and expected few difficulties here. The real demands on her skill would begin when she arrived above the orbits of Neptune and Saturn. At that point, she must descend to the ecliptic plane, where all the planets orbited, and intercept the ecliptic as close as possible to the orbit of Earth.

She took a single step, then another, and began to Walk steadily, while looking around. Once, a couple of icy-blue pinpoints of light flashed before her.

"I just saw two nano-blasts," she said.

Mr Morris replied. "There is some ammonia and methane in this area, only a molecule or two per cubic metre. It's just a bit of wear and tear on the ship, and our bodies too, I suppose."

"Ok."

Otherwise, everything seemed unchanged apart from her steadily declining distance counters, and a progress marker on her course map when she brought it up.

Gillian continued Walking.

IDENTIFY YOURSELF.

Gillian froze in shock, glanced about her, then checked all her instrumentation. Nothing was wrong. Automatically, she prepared herself for another step.

IDENTIFY YOURSELF.

The demand was soundless, language-less, a thought inside her head. But it was shouting. It was powerful; it demanded attention.

There was nothing to be seen or detected near the ship. Yet somewhere out there, an ancient sentinel had detected her presence as a Walker. She did not know how to respond to it. She dared not speak. Abel had encountered a similar sentinel, whose warning he had misinterpreted as a message from the sun.

"Gillian, are you ok?" It was Abel.

IDENTIFY YOURSELF.

There seemed to be no threat, no hint of menace. Perhaps all it wanted was a response, and nothing else.

"Yes, Abel, I'm just looking at the map, checking my orientation."

IDENTIFY YOURSELF.

Gillian sighed, gave up and focussed on her next step. She thought to herself, "I don't know how the hell I can respond to it, whatever it is. I'll just keep going."

STATE YOUR NAME, SPECIES TAG AND VESSEL.

Was that all? She only had to think in words to be understood? So she thought: Gillian Berry, Human, Starship Xing Long Hao.

SALUTATIONS: YOUR PRESENT COURSE FACES A LARGE MASS SURROUNDED BY CLOUD. YOU SHOULD AVOID IT UNLESS YOU INTEND RESEARCH IN THE VICINITY.

Measurements and other numerical data followed, all meaningless to Gillian.

Gillian reviewed the 3-D map prepared by her colleagues. It depicted a large, gassy comet on her present course, with a deviation scheduled before the ship got too close. She realised that any comet this gassy, so far from the sun, must have some other large mass responsible for its instability. It was a relief to see information on her map correlating with the sentinel warning. To take avoidance action for something that Mr Dryen and Mr Morris had not detected would have meant revealing the alien information source that she had encountered. She did not want to keep reminding everyone of her alien capabilities, although she knew that she must soon reveal this one, to protect other Walkers and their ships.

Abel spoke to her again. "Gillian, are you sure you're Ok?"

"Yes, Abel."

The incident had made her nervous, worried about herself, and the presence within her. She wanted to remain herself: Gillian Berry. She did not want to turn into some bizarre, possibly hostile alien. She knew she wasn't an alien being, a non-human.

But suddenly, Gillian felt more whole, more comfortable. Suddenly, she knew that her strange 'other' personality, the one with the child-like voice, had been absorbed. She did not know how she knew this, but she knew that it was true. The detached, observing part of her was still present, but she accepted that it was an aspect of her. She wondered if she would, or should, report this change to Mr McWhirter after the Walk.

As Gillian began her next step, she sensed a chirruping sensation inside her head. It terminated as she put her foot forward, then down, relocating the ship. Somehow, she understood what it was. The sentinel device had detected her parents as well as her, and had exchanged data with them. Gillian didn't know whether to be frightened or just curious about this incident, but in a few more steps she had reached her first turn point, the one intended to avoid the comet. The green arrow indicated a turn to her right of twenty degrees. She positioned herself accordingly, and stepped forward again, wondering how many other sentinels remained scattered around the solar system.

She wondered if Abel and Liam, as Walkers, had noticed anything just now, suspected the existence of the sentinel, but she dismissed the thought. They would have informed her. However, if either of them had been Walking today, they might have detected it, and misinterpreted its warning, perhaps disastrously, as Abel had on his last Walk.

She continued the journey. The orange-yellow star remained distant, and, she knew, would remain so until she was well within the orbit of Jupiter. Not until she reached a distance equivalent to the orbit of Mars, would she perceive an appreciable disk.

After two more course changes, she was approaching the orbital range of the Kuiper belt. Half an hour later, she was within the orbit of Neptune. She brought up the map again, and expanded it as she Walked. She saw the orbit of Neptune below her, as a slowly expanding ellipse. In the distance, within the ellipse of the Neptune orbit, those of Uranus and Saturn appeared. It was like gliding over an immense target wheel, with the sun, still a bright orange-yellow star, as the bull's-eye.

The scale of the map and of her operation, she realised, was becoming impractical. With the small distance left to run, her footsteps were getting too big.

Mr Dryen said, "Gillian, it will be time to commence the let-down towards the ecliptic plane in about five minutes."

"Yes, I see it coming up on my display."

In the distance, the orbit of Jupiter appeared.

"How are you feeling, Gillian?" Abel asked.

"Good, thanks. I'm going to change scale, to reduce the size of my steps."

"Ok."

Gillian performed the swimming motion gesture, watching the bull's-eye target wheel ahead of her expand, its circles seeming, momentarily, to rush towards her as the scale changed.

Suddenly, she became conscious of the great mass of the ship around her, aware that she was guiding an immense vessel containing several thousand people and cargo. She thought of her parents, waiting down in the second wheel, and of Celia and Liam, watching her from a few yards away.

Gillian was now well within the solar system, yet around her everything still appeared as empty as when she began her journey in interstellar space. Only her mask display revealed a more accurate reality. She continued, gazing at the orange-yellow star as she Walked. Five minutes later, Mr Dryen said, "Gillian, we're readying the engines for startup. You shouldn't notice anything, but tell us if you do. We want to be ready for vector adjustment as soon as you let us down into Earth orbit."

She crossed the orbit of Jupiter, passed over a few markings for the major asteroids, and saw the orbit of Mars appear. A moment later, she was above it.

She didn't feel tense, but she noticed that her mouth had become dry.

"Commence the let-down now, Gillian."

Ahead, the orbit of Earth appeared, displayed as a blue ellipse, blinking on and off, growing fast as she continued her Walk.

"I'm changing scale again."

"Ok, Gillian."

Off to one side, a small grey sphere replaced the orange-yellow star as she approached the blue ellipse marking Earth's orbit. It was the sun, shaded by the system to avoid distraction. The ellipse indicating Earth's orbit expanded rapidly and was soon almost below her. Gillian rotated her frame of reference to place it more directly ahead, no longer an ellipse, but now perceivable as an immense near-circle tilted at seventy degrees towards her. The location of Earth was marked as a blue spot, at one o'clock. Nearby, the L5 point appeared as a blinking cross.

She was now at maximum scale, maximum resolution of the system. The next few steps were her most difficult, requiring the most precision.

Gillian raised her arms above her head, and rose "En pointe" on the tips of her ballet shoes. "Here we go!" she chirped, making her voice confident.

She dance-stepped delicately towards the L5 point, watching it move closer and closer. Her footsteps were only a couple of centimetres long. She heard a few gasps from her audience in the Navigation Centre. These became cries of amazement when she went closer to the target than a distance of nine hundred thousand kilometres. And when she arrived at the orbit, she was still not finished. She rotated her frame of reference and followed the orbit horizontally, to get even closer to L5.

The blinking cross now ahead of her approached swiftly. Gillian continued, her steps becoming tinier and tinier, until the tips of her points were only moving a few millimetres across the stage. She stopped at a distance of four hundred thousand kilometres from L5, about the distance of the Moon from the Earth. Any closer would reduce the safety margin too much if she tripped.

At this point, she noticed the ship was plunging through the Earth's orbit and below it. It had the direction and speed resulting from its original vector in the Gliese System, combined with that from full power thrust during their journey through the cosmic vent fan. Gillian quickly adjusted her reference frame to a gentle slope and performed a tiny step to climb the ship back above Earth orbit by about thirty thousand kilometres. This would save time and fuel. At that moment, she sensed the stage beneath her feet seem to tilt slightly. The engines were coming on.

Gillian relaxed, and pulled her mask off. "Well? How did I do?" she demanded.

There was complete silence for a few seconds, before the Navigation centre broke into cheers and clapping. She almost bowed, like a ballerina, but just waved and smiled, feeling vindicated after her long confinement in the second wheel, Gillian felt the gentle surge of the ship's engines, at full throttle. In seven or eight days, they would reach the L5 settlement.

Abel said, "That last little correction was brilliant, Gillian!"

"Well done, Mr Berry!" the Captain said.

"Thankyou, Captain," Gillian replied. She wondered if he had forgiven her.

Mr Dryen announced, "I'm receiving a flood of queries. They thought our ship was destroyed, lost. And now we've suddenly reappeared. We've created a sensation!