"Citizens of Human Federation Underground City No. 1183, according to the latest observations, the sun will undergo a helium flash in thirty minutes."
"Human civilization has entered its final thirty-minute countdown."
"We... have failed."
In the underground city, five hundred meters beneath Earth's surface, a woman's somber voice played over the speakers installed everywhere.
Everyone who heard the announcement felt an indescribable sense of suffocation deep within.
Lü Yongchang sat expressionlessly in front of a holographic projection.
In the hologram, an enormous ball of fire burned silently in the depths of space.
It was a live image of the sun.
Lü Yongchang took a deep breath, raised his right hand, and made a gesture in the air.
The hologram abruptly zoomed out, revealing the entire Solar System as it now stood.
Unlike before, the Solar System was now missing two planets.
Venus and Mercury had already been swallowed by the sun!
And the sun had become a colossal, dark-red behemoth!
In astronomy, it had a specific name.
A red giant!
"Yongchang... are we-no, is humanity really going to end like this?"
A woman's slightly helpless voice came from beside him.
Lü Yongchang turned to look at her.
A woman in a white lab coat sat in a chair, staring blankly at the hologram before her.
Something flickered in Lü Yongchang's eyes.
As chief scientist of the Human Federation Academy of Sciences, he worked alongside this woman, Su Yutong, who was both his partner and his capable assistant.
"Yes. Humanity is finished."
Lü Yongchang sighed softly and continued, "We have twenty-odd minutes left. Would you like to go up and see the surface?"
Su Yutong's eyes stirred. She drew her gaze away from the hologram and slowly rose from her chair.
She reached up and let down her long black hair, then faced Lü Yongchang with a radiant smile.
"Of course."
Inside the elevator of Underground City No. 1183, Lü Yongchang and Su Yutong stood in heavy protective suits, looking at each other in silence.
On the elevator's screen, the number displaying their current depth kept changing.
A trace of wistfulness passed through Lü Yongchang's eyes.
In 2045 CE, the sun, on which humanity depended for survival, had been affected by an unknown influence. It had left its prime and entered old age ahead of schedule.
In just five years, the sun had entered its red giant phase and swallowed two planets in the Solar System, one after another.
Driven into a corner, humanity had set aside its differences and established the Human Federation.
And Lü Yongchang, an outstanding student since childhood, had overcome every hurdle to claim the position of chief scientist at the Human Federation Academy of Sciences!
According to his calculations, even if the sun entered its red giant phase prematurely, it would still take more than a century before a helium flash occurred.
Since the surface was no longer habitable, the Human Federation had built countless underground cities at his urging. All of humanity had taken refuge belowground while construction began on interstellar spacecraft.
But clearly, his calculations had been wrong.
In just five short years, the sun had raced through a life cycle that took other stars billions of years!
The helium flash was imminent!
Earth, now the closest planet to the sun, would inevitably melt into a ball of magma.
Human civilization had reached its end!
Ding!
"Esteemed chief scientist, may your research mission on the surface be a complete success."
A crisp notification tone roused Lü Yongchang from his thoughts.
He looked at the elevator screen.
518°C
That was the temperature on the surface outside.
The elevator doors slowly opened, and a wave of heat rushed toward them through the shimmering air!
As he looked at the enormous red giant overhead and the surface roiling with heat, Lü Yongchang felt a searing warmth even through his protective suit!
"One more minute until the helium flash."
Su Yutong's slightly cool voice came over the radio.
Lü Yongchang said nothing. He merely raised his head and looked at the sun through his filtering visor.
As a member of Earth's only advanced civilization, he refused to bow his head and await death!
"Do you know how hard I worked to become your assistant back then?"
"Do you know why I did it?"
Perhaps because the end had come, Su Yutong's voice was filled with acceptance. "Because I love you."
Lü Yongchang's pupils abruptly contracted.
The helium flash erupted!
White light of unimaginable intensity poured from the red giant toward Earth!
In an instant, Lü Yongchang lost consciousness.
Fluorescent green filled his vision.
A white line slowly extended, tracing a tree diagram against the fluorescent-green void.
Lü Yongchang stared at everything before him in bewilderment.
This... what was this?
A faint glimmer lit up at the bottom of the tree diagram.
Instinctively, he turned his gaze toward its base.
Nuclear Energy Control: Controlled nuclear fission.
A line of brightly highlighted white text appeared.
The next moment, the white area began extending upward.
Nuclear Energy Control: Controlled nuclear fusion.
As the previously dim line lit up, countless words and symbols instantly flooded Lü Yongchang's consciousness!
"Lü Yongchang! Lü Yongchang!"
"Professor Guan is calling you! Lü Yongchang!"
Through his daze, familiar voices called softly beside his ear.
His vision gradually came into focus.
A classroom came into view.
Looking at the elderly man on the podium, who was frowning at him, Lü Yongchang's pupils contracted slightly.
Professor Guan Hualiang!
Hadn't... hadn't he passed away five years ago?!
"Lü Yongchang! This is your first college physics class! If you dislike physics this much, why did you enroll in the physics department?!"
Anger tinged Guan Hualiang's voice.
Utterly bewildered, Lü Yongchang instinctively stood up and looked around.
The scene was familiar.
This was... his university classroom!
If he remembered correctly, this was his first physics class of sophomore year!
He hurriedly pulled his phone from his pocket and turned on the screen.
September 6, 2030!
Had... had he been reborn?!
In an instant, countless conflicting emotions surged through Lü Yongchang's mind.
Confusion, sorrow, loss, and a glimmer of hope!
"Mandated by Heaven, may you enjoy long life and eternal prosperity."
That was where his name had come from.
As it turned out, the name had been well chosen.
In his previous life, he had risen to the pinnacle of human achievement, but... his mistake had led to the complete extinction of human civilization.
In this life, he would put everything right!
But... how should he do it?
"Lü Yongchang! Did you hear what I said?!"
On the podium, Professor Guan Hualiang's face flushed crimson with anger.
In all his years teaching at Sandao Kou University, he had never encountered a student with so little respect for his elders!
Lü Yongchang looked up at Professor Guan Hualiang and the blackboard behind him, and something flickered in his eyes.
Perhaps... he needed a chance to make a stunning debut!
The very next moment!
Countless formulas and words from the fluorescent-green tree diagram whirled through his mind like a storm!
P.S. The first few chapters may have some off-putting plot points. This is also the author's first time writing a novel.
As for the female lead, she has almost no role, so you could say there is no female lead.
Updates every night at midnight.
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