Accel World: Floating Bridge in Starlight
“Low orbit…type.”
“The basic idea is the same as the geostationary orbit-type. But the structure is different. The central station of the Hermes Cord floats at a much lower location than geostationary orbit, at 2000 km above the ground…Though that’s still outside the atmosphere.”
“Eh…err, if geostationary orbit is 36,000 km high…isn’t that unreasonably close to the ground!?”
“It is close. Since the cable is also much shorter at that height and can thereby be made lighter, the weight for establishing balance does not need to use something like an asteroid either.”
“A-Aah…I see…”
After nodding his head deeply, Haruyuki voiced a natural question.
“…Then, why didn’t they plan to use the low orbit-type from the beginning?”
“That’s because there’s a problem with it. A man-made object placed at low orbit…in other words, from 1500 to 2000 km above the ground, has to orbit at a speed that far surpasses the Earth’s rotation, in order to obtain the centrifugal force needed to balance the much greater attraction of gravity there than at geostationary orbit. For a geostationary orbit-type elevator, the lower end of the cable can be fixed onto the ground because the speed of its orbit synchronizes with the Earth’s rotation, but a low orbit-type cannot do that.”
While saying that, Kuroyukihime extended her finger and struck a small mark very close to the circle that represented the Earth.
“This is the Hermes Cord’s central station, built at an orbit of 2000 km high. A cable made out of entwined carbon nanotubes stretches out from it both above and below, and this cable is connected to a top station that acts as the weight attached to the top end and a bottom station attached to the bottom end.”
The bottom end of the line that extended upwards and downwards from the mark was just a little ways away from the outline of the Earth. Pointing at the gap between them with her finger, Kuroyukihime continued.
“This bottom station floats 150 km above the ground. If it was lower than that, the atmosphere would become too dense and the whole elevator would be drawn tight due to friction, and eventually fall to the ground.”
“Ha—……”
Letting out a long breath, Haruyuki spoke in order to put his thoughts in order while twitching his pig nose slightly.
“In other words…err, the Hermes Cord is an artificial satellite with a length of 4000 km that is connected to these three stations by a CNT cable…right? And this orbits the Earth at a much faster speed than the Earth’s own rotation…?”
“Exactly. Since the ground speed of the bottom stations reaches Mach 10, the low orbit-type elevator is also called by the nickname «Hypersonic Skyhook».”
“But then, what about…the fact that it was built in the sea near Christmas Island in the east Pacific Ocean? I have memories of looking at the huge man-made island on the news at the time, but…doesn’t the long tower surely extend up from there…?”
“That island is a base for the arrival and departure of space planes that carry people and materials to and from the bottom station of the Hermes Cord. The planes that take off from there rendezvous with the station at 150 km above and drop off cargo there. Then, the cargo is lifted up inside the elevator until it reaches the top station at 4000 km altitude, and then it is carried from there to a geostationary orbital station or the international base on the moon’s surface by a round-trip shuttle. Incidentally, since the geostationary orbital station is also right above the arrival-and-departure base, even if people say «the Hermes Cord is in the east Pacific Ocean», it’s not really incorrect.”
“Hofuu…”
Letting out a sigh for the nth time, Haruyuki looked at the window diagram anew. Since the Earth’s diameter was about 12,700 km long, comparing it with a 4000 km length could be considered as the same as the proportion between an apple and its stem, but the idea of such a thing flying overhead at Mach 10 was very difficult to take in.
“Hmm, somehow, I’m scared that it will fall due to some kind of rebound.”
When he murmured that without thinking, Kuroyukihime shrugged her shoulders lightly.
“Actually, there was someone who tried to make it fall as well.”
“H-Hah!?”
“What, you don’t know? From what I remember, there was a case at around the beginning of spring where a terrorist that had slipped in among some tourists tried to set a bomb in the central station. Due to that, it was decided that the Hermes Cord’s security system would be strengthened, and Japan was also participating in the bid for constructing the system, so it’s connected to the recent news about the first export of the social camera technology.”
“Uwah, so that’s how it was. I’m sorry, I haven’t been diligent with the news…”
Just like the times he was nominated to speak up in class and he couldn’t answer properly, Haruyuki hanged his head. However, Kuroyukihime didn’t scold him any further, and continued her explanation with a wry smile.
“The low orbit-type elevator Hermes Cord has a small and thin cable compared to that of a geostationary orbit-type. Its design is tight. That’s why, even if a bomb of a size that could fit in a pocket went off, it could cause tremendous damage depending on the location of the explosion. There is also no spare electric power or space for accommodating a large-scale surveillance system in it. I think that is the reason they adopted Japan’s social camera technology…Yeah, with this we can finally return to our original conversation.”
Letting out a long breath, Kuroyukihime waved her right hand’s fingers and opened up the VR operating menu. She materialized two glasses and presented one of them to Haruyuki.
‘Damn it, I should have prepared something like that as the one that called her here!’ Despite inwardly panicking like that, he accepted it and took a sip. Seemingly an original drink that had countless flavor parameters fine-tuned into it, it was unlike any drink in the real world, and yet a fresh bitter-sweetness without any unnatural quality to it spread throughout his taste buds.
“It’s…It’s very delicious.”
When he said that, Kuroyukihime gave a small smile and then nimbly extended out her avatar’s left hand.
“I’ve also recently been doing real cooking practice, but…A task that you can’t just do over again is really troublesome. Did you know, Haruyuki-kun, light-coloured soy sauce’s only difference is its lighter color! What’s with that, is it supposed to be like salt water!?”
“H-Heh, I didn’t know that…Or rather, why are you suddenly trying to raise your cooking skills…?”
“That’s obvious, it’s so that, one day, for yo…”
Suddenly closing her mouth at that point, Kuroyukihime gave a big cough.
“…It’s just for recreation[17]. More importantly, let’s finally get back onto the main subject.”
Following her slightly forceful change of topic, she continued her rapid-speech explanation.
“I said that the Hermes Cord doesn’t have the room to accommodate a large-scale surveillance system as well. So it became the turn of Japan’s social cameras. That system collects in one place the images photographed by countless cameras through an exclusive high-speed network, and signs of criminal activity are detected by automatically analyzing them with a super high spec supercomputer. For example, if a gun were detected by a camera somewhere, the system would immediately analyze where the person who has that gun is and where they came from, and then continue tracking where they go. The locations of the facilities where this processing is performed, the «Social Security Surveillance Centers», have not all been revealed to the public.”
“E-Even you don’t know, senpai?”
When Haruyuki seriously asked that, Kuroyukihime gave the greatest wry smile yet.
“Hey, just what do you think I am? I’m only a frail female middle school student, there’s no way I would know the greatest of our nation’s state secrets such as that! …Well, I do have some guesses, though.”
 
; “W-Where!?”
“That’s a secret…More importantly, just as I explained just now, the social cameras gather the automated image analysis that acts as the guts of the system at the SSSC and process it there. In other words, neither huge recording equipment nor human operators are required for the surveillance cameras usually. Supposing that that very «simplicity» is the reason it was adopted for the Hermes Cord in this case…you could say it’s inevitable that the space elevator’s cameras and Japan’s social camera network are linked.”
*POKAAN* As Haruyuki was listening attentively to these words, Kuroyukihime gave a wink as she said the word ‘connected’ as if she were waiting for something, and then Haruyuki finally remembered the main purpose of this sudden Dive Call.
“Ah…I see, err, so the fact that they’re connected means, in other words, umm…”
While flapping his pig avatar’s short arms, he shouted,
“…we can go there!? To the Hermes Cord in Accel World!!”
“Hmm…Well, we’re only at the stage where we can’t say it’s impossible yet, though.”
Giving a mischievous smile, Kuroyukihime continued in a tone as if she was somehow testing something out.
“First, there is the question of whether Brain Burst, a dueling game, will faithfully extend its stage all the way to there. And even if the networks are connected, how would we go all the way there? We Burst Linkers, generally, Dive in at the places where our real bodies are. In other words, in order to go to the Hermes Cord in Accel World, it would be necessary to actually board the space elevator on this side. Tour packs for going up to the geostationary orbital station have also been put on the market these days, but it’s expensive.”
“…They’re super-expensive, aren’t they…”
Haruyuki dropped his shoulders. He considered for an instant that as Silver Crow, with his wings, he could fly up to the bottom stations above after Diving on the ground, but he dismissed the idea before even voicing it. The limit to the altitude Crow could reach was at most 1500 meters. On the other hand, Hermes Cord floated in the sky a hundred times higher than that, at least 150,000 meters high.
No, before that, he couldn’t even go to Christmas Island, the terrestrial space plane departure base, with a middle school student’s pocket money at all.
“Hmm…so in other words, unless you’re a super-rich kid, there’s no way to Dive in at the Hermes Cord…”
“Or rather, if you could go to the actual thing in the real word, I don’t think there’d be any need to go through the trouble to Dive into the reconstructed article in Accel World.”
“That’s…true.”
*HAFU* Giving a sigh of disappointment this time instead of admiration, Haruyuki looked up at the sky.
Even when seen from the top of a 500 meter tall tower, the virtual blue sky seemed as if it were far away and went on forever. No, in such a VR Object Set that’s freely distributed to the public, the «sky» would not reach higher than 10, or maybe 100 times the height of this tower. That was because there was nothing «beyond» this blue sky. This was a closed world, where nothing but the thin blue color continued on past it.
“…Haruyuki-kun.”
Hearing his name suddenly called, he turned his face back down, and met his gaze with Kuroyukihime’s gentle yet somehow mysterious-seeming eyes.
“Why do you want to go to the Hermes Cord so much? Compared to how you can fly freely with your wings, the space elevator is only a man-made object that goes around a decided orbit, after all.”
“Eh…err.”
Having been thrown an unexpected question, it took several seconds for Haruyuki to form the ambiguous thoughts inside him into words.
“Umm, of course, there’s the reason that I simply like high places as well, but…also, I was thinking that, supposing it was possible to go there, that person’s wish might be fulfilled even just a little. That person…who has always aimed for Accel World’s sky, no, for «beyond it».”
The instant she heard that—.
Kuroyukihime’s eyes widened slightly, and then her eyelashes turned down.
The words that eventually came out of her lips were so quiet, it was almost as if they were thoughts themselves.
“……I see.”
After murmuring that, she turned her gaze towards the light blue sky.
“That’s true…Her passion for the sky has surely not disappeared even now. Just as maddeningly as I aim for Level 10, no, even more so, she should be wishing to struggle on and reach the other side of that blue color…”
“……Yeah.”
Nodding, Haruyuki also turned his face upwards once again.
That person—a core member of the first «Nega Nebulous», and a Level 8 Burst Linker, «Sky Raker».
Having lived in seclusion on the Old Tokyo Tower in Accel World for a long time, she had rejoined the reborn Nega Nebulas, reformed after three years, two months ago.
However, it was a little different from a complete return to active duty. Demonstrated by how she had refused Chiyuri’s invitation this evening, she didn’t do any normal duels at all, participating only in the «territory matches» every weekend, and furthermore she never came out onto the front line. She always remained on standby at the back and concentrated on positional defense.
Of course, Haruyuki, and probably Takumu and Kuroyukihime as well weren’t dissatisfied with that playing style at all. That was because Sky Raker, who moved through means of a wheelchair, generally couldn’t run except on paved roads or smooth ground. Also, she accomplished splendid success in battle when defending her position through her original fighting style of freely manipulating her wheelchair and letting out hand-slash attacks while toying with her enemies. If the enemies were mainly close range types, she could fight sufficiently even when in a team of three where there was only one attacker and she had to protect the team healer almost perfectly.
Compared to the time where they had barely endured the hour-long territory matches with a team of just Kuroyukihime, Haruyuki and Takumu from autumn to winter last year, the battle power of the current Nega Nebulas had improved by leaps and bounds. That was without a doubt.
But, there was one clear fact that no one had tried to voice out loud.
If Sky Raker were to undo her seal on her Enhanced Armament «Gale Thruster» and wear it on her once again, her fighting power should leap up several, dozens of times greater than that of now. Even if she had lost both her legs, Haruyuki had proved that a mid-air dash through its booster propulsion displayed a huge offensive strength when he had driven away a huge enemy in the past with it.
However, even after Haruyuki had returned the Gale Thruster he had borrowed from her, and even when faced with losing battles, Sky Raker hadn’t tried to summon. As if she was stubbornly denying the «wings» created by her own heart.
“……I.”
Grasping his hands together in front of his round belly, Haruyuki whispered.
“I’m not particularly thinking something like, ‘the legion will become stronger if that person flies again’. It’s just…if Raker-san doesn’t believe in her wings, I want to convey her that it isn’t so. Having borrowed «Gale Thruster» once, I understand…Certainly, compared to Silver Crow’s wings, that Enhanced Armament’s flight time is short and therefore the altitude it can reach is also low, but its instantaneous output is more amazing than the acceleration of any other kind of avatar…That’s why, there is actually much more power hidden inside it. I believe that.”
After thinking and thinking, and then finishing his hard-fought explanation, Haruyuki raised his head and met with Kuroyukihime’s eyes, which were filled with an unusually kind yet plaintive feeling.
The swallowtail butterfly avatar slowly nodded once, and then spoke in a quiet voice.
“If Raker can be taken to Hermes Cord, you can convey that to her…is that what you believe?”
Haruyuki also nodded, while being aware that he was saying something too romantic-soundin
g.
“Yes…Umm, that is if what I’m thinking is correct, though.”
“Geez, how about you declare something while full of confidence once in a while?”
After immediately giving a wry smile, Kuroyukihime took a single deep breath, and then once again started speaking.
“—Just as I explained earlier, the Hermes Cord in the real world orbits at an altitude of at least 150 km. Therefore, even if the newly installed social camera network there is connected to the one in Japan, I believe that the Hermes Cord in Accel World will naturally appear at the same height. It’s a distance that no kind of duel avatar could reach…but, I think getting there using a means of transportation is just possible.”
“Eh…Eeh!?
Letting out a high-pitched voice, Haruyuki leaned his body forward. As he was on the verge of falling off his chair, Kuroyukihime caught his flat nose with the tip of her high-heel shoe to stop him.
“I’m just talking about a possibility, calm down a bit.”
“Y-Yessh…”
“Listen well, even if Brain Burst’s origins are wrapped in mystery, it’s still a dueling game on the surface. Therefore, when a new stage is added to that world, don’t you think it would be truly irrational if it was a place that no one could go to?”
Grinning, she moved her index finger as if inviting him.
“If we assume that, then it wouldn’t be strange even if a method of transportation, one that can only be found by those who think very hard and search for it, secretly appears somewhere in Accel World.”
“Secretly…huh.”
“Even normal RPGs have them, right? Things like treasure chests that seem unobtainable at first glance, but a route to attain it can be found if you observe the map carefully and use your head.”
“Ah, there are, there are. Those kinds of things are my favorite.”
After nodding vigorously at Kuroyukihime’s example, Haruyuki looked carefully at the diagram Kuroyukihime had drawn.
The space elevator that orbited at an altitude of around 150 km. Considering it, he couldn’t think of any methods of going there besides a space plane or a rocket. If there were to be a place in Japan where a rocket would be launched—