STAR I: Protein Behavior
Book One of the STAR Trilogy
Preface
If we could see every star, the night sky would be filled with light. There would be no darkness.
This is known as Olbers' Paradox, an old riddle in astronomy. If the universe is infinite, then in whichever direction you look, there should be a star. So why is the night dark? The answer lies in the age of the universe and the speed of light. Above us, there are far more stars whose light has not yet reached us — invisible stars — than stars we can see.
The history of humankind has always been a journey toward the invisible.
Once, there were those who pushed their boats into the winter sea, toward a horizon beyond the wind. Why did they head for a sea from which there was no return?
This is the story of the 0.3 percent of people who are fated not to fear the unknown, but to ache for it. Led by an invisible map written into their genes, three generations connect their lives from Tokyo to Mars, and then beyond the solar system. I invite you to witness, with them, the color of the stars they found on the other side of darkness.
Prologue Poem
If every star were visible
the night sky
would be filled with stars
and there would be no darkness
There are that many planets
The universe is that vast
And that distant
Humankind
has finally begun
to slip free of this star
And someday
we will
migrate to other stars
Prologue: The Map of Stars
If we could see every star, the night sky would be filled with light and there would be no darkness.
This is called Olbers' Paradox. If the universe is infinite and stars are evenly distributed, then no matter which direction you look, your line of sight should end on a star. And yet the night sky is dark. The answer to the contradiction lies in the age of the universe and the speed of light. There are stars whose light has not yet reached us. There are far more stars we cannot see than stars we can.
Humanity has always aimed for the invisible.
PART ONE: THE BLOOD OF VOYAGERS (Tokyo, 2031)
Chapter 1: The 0.3 Percent
So Kamishiro learned that he belonged to 0.3 percent of humanity in the spring he turned nineteen.
It wasn't a doctor or a genetic counselor who told him. It was an email on his smartphone. The sender called itself the Protein Behavior Foundation.
The subject line was simple:
"You have been selected."
He almost deleted it as spam, but paused. He vaguely recalled checking a third-party data sharing consent box during a screening for a job application three months earlier. Attached was his genetic analysis data. A mutation in the CHRM2 gene, a specific haplotype of DRD4, and NOVA1 — a gene coding for a protein that regulates neuronal plasticity — an extremely rare combination of all three.
According to the Foundation, roughly three in a thousand people express all three at once.
So's father had been a fisherman. In a small port town in Hokkaido, he took his boat out even on stormy nights. So had once asked, "Aren't you afraid of the sea?" His father laughed. "That's what makes it interesting."
His father never came back from a rough sea in the winter So was fourteen.
The email included an invitation to an interview. The location was a glass-walled building in Minato, Tokyo. So hit reply and accepted.
The woman waiting at the Foundation's reception wore a white lab coat. She looked to be in her mid-thirties, her eyes quiet behind her glasses.
"Kamishiro So? I'm Azusa Kirishima, lead researcher."
She didn't offer a handshake. Instead she held out a small terminal. A spiral graphic rotated on its screen.
"Look at this part of your genes."
So peered at it. Three strands entangled in a strange shape.
"It's a variant of NOVA1. The three-dimensional structure of the protein is different from the norm, which creates an unusual pattern of neural connectivity. Specifically—" Kirishima paused. "Your stress response to novel environments is reversed compared to most people."
"Reversed?"
"Most people feel fear in the face of the unknown. People like you feel excitement."
So thought of his father's words. That's what makes it interesting.
"What does the Foundation do?"
Kirishima put the terminal away and looked at him.
"We're preparing to send humanity off this planet."
Chapter 2: Under the Foundation
The headquarters of the Protein Behavior Foundation spread across three basement floors beneath an eighteen-story building.
So was led to a lab on B2. There were thirty-two young people gathered from around the world, aged eighteen to twenty-five, from seventeen countries. They were all 0.3 percent.
"We call you Protein Behaviors," Kirishima said. "People whose proteins behave unusually. But also, people who embody the most primal behavioral pattern of the human species itself."
"Migration?" asked a young Brazilian man a few seats ahead in English. "Where to?"
"First, Mars," Kirishima answered. "But that is only a waypoint."
A star chart appeared on the screen. The solar system, and arrows extending beyond. Alpha Centauri, Epsilon Eridani, Tau Ceti.
"One of you, or one of your descendants, may someday stand on those stars."
Someone inhaled sharply.
Next to So sat a Japanese woman with black hair. Her name was Rin Moriya. A third-year in the Department of Aeronautics and Astronautics at the University of Tokyo, sharp-eyed, scribbling rapidly in a notepad.
"Do you think they're credible?" So whispered.
Rin looked up. "I already checked their funding. Three aerospace companies, a Swedish institutional investor, and one anonymous individual. Whether they're credible depends on what they're trying to do."
"Why did you come?"
Rin looked forward again. "I want to design a starship."
That night So went up to the roof of the dorm. Tokyo's night sky was badly washed out. Almost no stars were visible.
He thought of the Hokkaido sky he used to see with his father. The density of the Milky Way that summer when he was ten, when he first understood what people meant by a sky full of stars.
The universe is vast. That many planets. That far away.
And now he was standing at its threshold.
Chapter 3: Training
The Foundation's program was brutal.
Wake at 05:00, physical training. Mornings: lectures on space medicine and life-support systems. Afternoons: practical training in each person's specialty. Evenings: languages and space law. Once a week, psychological evaluation.
So was assigned to extravehicular activity and geological survey. When he asked why, Kirishima said, "Your data shows high decision-making ability in isolated environments and fast adaptation to physical work. And your threshold for curiosity overtaking fear is especially low."
"Are you complimenting me?"
"I'm stating facts."
After three months, he started talking with Rin. She never once dozed off in class. She ate the bare minimum and was always calculating something.
"Do you sleep?" So asked one night.
"I do, but I don't want to," Rin said. "I can't design anything in my dreams."
"What is a starship to you?"
Rin thought for a moment. "My parents were engineers. They died in the Tohoku earthquake. I was eight."
So fell silent.
"This planet can be terribly cruel sometimes," Rin went on. "But space is even crueler. That's why it's worth confronting."
Six months into the program, they went to Tanegashima for their first hands-on training. A joint facility with JAXA. There stood the next-generation crewed rocket, Akatsuki. Seventy-two meters tall, three stages, six liquid hydrogen engines on the first stage. Capable of reaching lunar orbit.
So looked up at its bulk and felt his heart hammer.
It wasn't fear.
PART TWO: RETURN TO THE GREAT OCEAN (Mars Orbit, 2041)
Chapter 4: The Red Planet
The sky of Mars was salmon pink.
So saw that color for the first time through the small window of the EVA hatch. Atmospheric pressure was about one percent of Earth's. Almost no oxygen. Daytime surface temperature below minus twenty Celsius.
But it was beautiful.
So Kamishiro was twenty-nine now.
Twelve people selected from the Foundation's program had boarded Akatsuki II as the first crewed Mars expedition team seven months earlier. At the moment they left Earth, So had watched the blue planet through the window. So small, and yet so heavy.
Rin Moriya was on the same crew. She was in charge of structural design and had been inspecting welds until just before departure.
The Mars base, Akebono, was set up three hundred kilometers southeast of the base of Olympus Mons. Three modules, solar panels, a drill rig. An orbiter had already confirmed water ice underground.
So's job was geology. Every morning he put on his suit and went outside. Collected samples, analyzed them. Communication delay with Earth was up to twenty-two minutes. If something went wrong, no one could come quickly.
"Aren't you scared?" Rin had once asked him.
"That's what makes it interesting," So said.
Rin laughed dryly. "Straight out of your genes."
One morning So found a strange pattern in the bedrock seventeen centimeters below the surface. A regular, layered structure. It looked like banding created by biology.
Chapter 5: Discovery
Analysis took three weeks.
It was on the one-hundred-and-thirtieth day after landing that the captain, Shuichiro Tanabe, gathered everyone in the conference room.
"I have a report," said Azusa Kirishima, who was with them as lead researcher. Her voice was calm, but trembling faintly. "We've confirmed an anomalous bias in the carbon isotope ratio in the bedrock sample So collected. Specifically, the C13 to C12 ratio falls within the range consistent with biological processes."
No one spoke.
"This is not direct evidence that life once existed on Mars. But we have no basis to deny it either."
"How old?" Rin asked.
"From a stratum between 3.5 and 4.0 billion years old."
3.5 billion years. Around the time the first single-celled organisms were born on Earth.
That night So went outside.
In the Martian night sky floated Phobos and Deimos. Two moons, irregularly shaped. And stars. Far clearer than from Earth.
Each one of those lights might have planets orbiting it. On those planets, something might once have lived.
Or might still.
So thought of his father. The man who rowed out beyond the sea.
Maybe 0.3 percent of any species always heads for the next horizon. Not a blind impulse, but the memory of life itself. Like single-celled organisms crawling onto land. Like fish growing legs. Like humans crossing oceans.
Now it was time to cross the sky.
Chapter 6: Storm and Choice
A Martian dust storm is on a different order of magnitude than Earth's.
On the one-hundred-and-eightieth day after arrival, a storm formed in the southern hemisphere on the far side from the Sun. Within days it grew to global scale. This phenomenon, called a dust storm, can sometimes last for months. The power output of the solar panels dropped by ninety percent.
"We won't have enough power," Tanabe said. "Even at maximum output of the geothermal generators, we have sixteen weeks. The resupply ship from Earth will arrive in twenty-one weeks."
Five weeks short.
"Something has to be cut."
There were three options. Lower the heat and put almost everyone at risk of hypothermia, cut food and water production to the bare minimum, or have half stay at the base while the other half made an emergency return.
So volunteered to stay.
Rin raised her hand too.
"You go back," So said. "If the designer doesn't go back, the next mission will be delayed."
"That logic should be coming from me," Rin said. "Without me, you can't do emergency repairs on these modules. You should go back."
They stared at each other for a while.
"Let's play rock-paper-scissors," Rin said.
So laughed. "In space?"
"Thirty thousand years of human wisdom."
Rin won. So stayed.
Captain Tanabe looked at So, then at the psychological and field-adaptability metrics on his screen. "Kamishiro... your isolation tolerance and environmental stress response data are the highest in the team. Logically, you staying gives the base its best chance." He nodded slowly. "The decision is approved."
The day the return vehicle left Mars, So watched its hull grow small through the hangar window. Rin's face, over the comms, kept calculating something until the very end.
In the storm, So kept recording. Changes in bedrock, atmospheric composition, groundwater movement. He was afraid. But his thirst for data that could only be found here was stronger.
He wondered if his father had been the same. In the stormy sea, reading the pattern of the waves.
PART THREE: THE INVISIBLE SEA (Beyond Saturn's Orbit, 2089)
Chapter 7: The Granddaughter's Era
Kake Kamishiro was seventeen when she read her grandfather's journal.
Her grandfather, So Kamishiro, became a director of the Protein Behavior Foundation after surviving Mars. He married Rin Moriya, and they had one daughter. Kake was that daughter's child — his granddaughter. So died of old age when Kake was seven.
The journal described his days on Mars. Records of the storm, sketches of bedrock, diagrams of the carbon isotope pattern he had found. And the final entry:
"Someday, someone will stand on the stars beyond. It may not be me. But if something of the color of the stars I saw remains in someone's blood, that will be enough."
Kake's genetic results arrived two weeks earlier. CHRM2, DRD4, NOVA1. All three.
Kake was a Protein Behavior.
In 2089, humanity had a frontline base at the outer edge of the solar system. There was a permanent habitat on Enceladus, a moon of Saturn, and a launch platform for interstellar exploration was under construction in orbit around Uranus. Mars was already a settlement of more than thirty thousand people, with its own autonomous government.
The Protein Behavior Foundation had also changed. No longer a small foundation, it had been reorganized as the Interstellar Exploration Agency, a quasi-agency of the United Nations.
Kake's invitation didn't come from the Foundation's successor. It came from the Exo-Ark Project — the largest project in human history, aiming for interstellar flight.
Chapter 8: Exo-Ark
The Exo-Ark Project headquarters were underground on Enceladus base.
With Saturn's massive rings outside the window, Kake received her first briefing.
"Alpha Centauri B is about 4.37 light-years from Earth," the briefing officer said, expanding a 3D map. "With current technology, we can travel at twelve percent of the speed of light. The journey will take about thirty-seven years."
"Thirty-seven years," someone muttered.
"The crew will hibernate for the duration. Conscious flight will be only for the first and last few years."
Kake raised her hand. "Can we come back?"
The officer paused for a moment. "It's one-way."
The room fell silent.
No return. Not to Earth, not to Mars. Forever.
Kake looked out the window. Saturn's rings glittered in the light. It had taken humanity centuries to get here. The first human to point a telescope at those rings could never have imagined that people would one day live beside them.
She wasn't afraid of not returning.
She did feel lonely.
"My grandfather—" Kake began. "When he was in a situation where he might never return from Mars, he kept recording. He wrote that he was afraid. But his thirst for what was only there outweighed it."
She faced forward. "I'm the same."
The selection process lasted a year. The first Exo-Ark crew was capped at two hundred and forty. More than sixty thousand people applied from around the world. Not just genetics, but technical, psychological, and medical aptitude were rigorously screened.
Kake was selected.
Chapter 9: Departure
Departure day was in the spring of 2094.
Exo-Ark 1 left the launch platform in orbit around Uranus. Three hundred and twenty meters long, eighty-six thousand tons. Sixteen nuclear pulse engines. Two hundred and forty crew. And inside cold-sleep pods, thousands of seeds and fertilized eggs and an archive of human knowledge.
The night before departure, Kake recorded a message to Earth. Nearly three hours for the signal to arrive across the vast void. Six hours for a reply. From now on, that delay would only grow until it never arrived at all.
"To Grandma. To Rin Moriya. The engine of the ship you designed is still the foundation of everything we have. I have read Grandpa's journal over and over. I can only imagine the color of the Martian sky he saw, but I am walking the road beyond the road you both walked. Since ancient times, the descendant of someone who once rowed into an invisible sea sets out again for a new sea. To the other side of the invisible sea. I cannot come back, but I have no regrets. Surely there too, there is a color of stars that can only be seen there. I love you."
The ship began to accelerate.
Saturn's rings grew distant.
The Sun grew small.
Only stars remained in the darkness.
Before entering her hibernation pod, Kake looked out the window one last time.
Countless stars. Far more stars whose light has not yet reached us.
Kake knew that her great-great-grandfather had been a fisherman. A man who took his boat out even on stormy nights. A man who said, "That's what makes it interesting."
That blood was in her now.
It was an invisible map made of genes.
The pod closed.
As her consciousness faded, Kake thought of one thing.
When I get there, I'll look at the night sky first. The sun seen from there will be just one star. But inside that light, Earth and Mars and Enceladus will all be contained.
There are more invisible stars than visible ones. And yet, there are stars.
The universe is vast.
That many planets, that far away.
So, we go.
Epilogue: At the Speed of Light
Thirty-eight years later, Exo-Ark 1 began to decelerate in orbit around the third planet of Alpha Centauri B.
Kake Kamishiro was fifty-five.
Outside the window, a blue-tinged planet was visible. It had an atmosphere. Prior surveys had confirmed evidence of liquid water. Signs of life were still unknown.
But it was beautiful.
She recorded a message to Earth. More than four years for it to arrive. Eight years if a reply came. She might not be alive then.
But someone would come. Her children might be born on this planet. Their children might head from this planet to the next star.
"To everyone on Earth, and everyone on Mars. We have arrived. There are stars here, too. The invisible star is now outside our window. As my grandfather wrote on Mars: there are more invisible stars. But if you go, you can see them. That's all there is to it. And that is enough."
After stopping the recording, Kake smiled quietly.
She had thought, When I get there, I'll look at the night sky first.
And now, the sun seen from here was just one star.
Inside that small light, everything was contained.
Night came.
A new night, on a new star.
With countless stars filling the sky.
Afterword: In Place of an Afterword
Olbers' Paradox was proposed by the 19th-century German astronomer Heinrich Wilhelm Olbers. If the universe is infinite and static, the night sky should be filled with stars in every direction and be as bright as day. But in fact, the night sky is dark. The answer lies in the age and expansion of the universe — there are countless stars whose light has not yet reached us.
The question at the heart of this book is this: The world is still full of things we don't know. There are more invisible stars than visible ones. There are more places we've never been. And that is why we can keep having a reason to go forward.
The concept of "Protein Behavior" was inspired by research on novelty-seeking behavior in behavioral genetics and by hypotheses linking specific gene variants to human migratory history. This book, however, is fiction, and I have prioritized the poetic impulse of "somewhere that isn't here" over scientific rigor.
In ancient times, our ancestors who rowed out toward an invisible sea beyond were surely not fearless supermen. They must have been ordinary people, gripping their rudders with trembling hands, choosing to go forward anyway. I don't think they were not cowardly. They were cowardly, and they went anyway. The gradation of that blood leads to us, here and now.
There are stars. Even if you can't see them, they are there.
I hope that simple impulse will remain a small lamp for humanity living in a cold universe.
So, we go.
