Bidding farewell to their adoptive parents, Li Xu and Yan Maolin went to Nanjing University of Aeronautics and Astronautics together. Outside the bus, there was a drizzle of rain, two or three pedestrians riding shared bicycles in the wind and rain, surrounded by verdant cedar trees, everything was so comfortable.

The bus stopped at the Ming Palace Station, and the two entered China Southern Airlines with an umbrella. Li Xu looks petite compared to Yan Maolin, and now he is even more held in Yan Maolin's arms.

"You should buy a bigger umbrella." Yan Maolin held an umbrella, as if explaining.

"Hmm." Li Xu involuntarily lowered his head, and his face gradually turned crimson.

Walking through the towering French plane tree, the two came to the lecture hall of China Southern Airlines. You only need to swipe your ID card to enter the lecture, but even then there are very few people who come. After all, there can't be too many people who are interested in "Egg to Sperm Technology", and there are almost no people like Li Xu who dream of eliminating women's fertility pain.

Although Li Xu's family is supportive, others are not optimistic about Li Xu's dream. Therefore, Li Xu is very introverted, and the only person who can confide in him is Yan Maolin.

Li Xu listened to the report and recorded the content of the report. As a high school student, it is difficult for Li Xu to understand these technical terms, but even so, she still tries hard to understand and record, anyway, she can be admitted to university and graduate school in the future.

"Boom." Outside, the rain was getting heavier, and the sky was becoming overcast, as if it was approaching night. The rain "roared." The sound of hitting the ground made the hall quieter.

Yan Maolin quietly peeked at the girl who was struggling to write beside him, her white eyes were on the bridge of her small nose, and her eyes were fluttering one by one, looking extremely cute. Her hair runs through her ears and is tied back in two ponytails. Yan Maolin liked his sister's double ponytails the most when he was a child, and he always grabbed Li Su's hair involuntarily.

This time, looking at his sister who was still a double ponytail, Yan Maolin gradually became moved, and couldn't help but reach out and pinch Li Xu's ponytail and gently rub the green silk. Li Xu's hair is very healthy, green silk like brocade, it feels like silk, and I can't help but put it in front of my nose to smell, and there is a hint of shampoo fragrance.

Just as Yan Maolin was immersed in the fragrance of his sister's hair, Li Xu's face was already red as an apple. She didn't know what she was writing at all, her heart was in a mess, her whole person was dizzy, as if heaven was like a dream, very comfortable. Li Xu hopes that this feeling will continue, that time will stop.

"I'm sorry, Xiaohu." Yan Maolin discovered his gaffe in time.

"Hmm." Li Xu seems to have fallen from heaven to hell, and he has lost a lot.

"Brother......" Li Xu wanted to say something to Yan Maolin, but he couldn't say anything when he saw his handsome face. The gap is too big.

"What's wrong? Silk. Yan Maolin said.

"It's nothing......" Li Xu pursed his lips and shook his head.

"If you have anything on your mind, just tell my brother!" Yan Maolin stretched out his hand and wanted to rub Li Xu's hair, but he took it back halfway when he thought of what had just happened.

"When is my brother going to fall in love?" Li Xu bit his lip lightly and asked worriedly.

"You fall in love first, and then I fall in love." Yan Maolin was silent for a while, then looked at his sister and said.

"Hmm." Li Xu felt a lot more at ease, she wouldn't like others, but suddenly blamed herself, if Brother Lin couldn't get married because of herself, it wouldn't be good, and then shook her head.

"Then how about I have to get a girlfriend with Xiao Su's consent." Yan Maolin smiled.

Li Xu looked up and saw Yan Maolin's clear eyes, and became happy again, "Hmm." ”

Gradually, the rain stopped. The gloomy sky brightened again, the dark clouds drifted away, the sun returned to the earth, and the sky built a rainbow bridge.

"Let's go, the rain has stopped." Yan Maolin Road.

Suddenly, Yan Maolin saw a white scratch appear in the blue sky, like the wake of a jet plane. But then, one after the other, and in more than one direction.

Yan Maolin, like other boys, has military and aerospace hobbies, and the college entrance examination he prepared for was China Southern Airlines. He knows everything from the launch and construction of the Curiosity rover, the Chang'e program, Mars 2020, the Chinese space station, and the Deep Space Gate orbital station. He never let go of every issue of the military magazine.

Seeing these trajectories, Yan Maolin can be very sure that it is the trail of the missile. And so many wakes mean a fact.

The pupils shrank, and the brain almost stopped thinking, leaving only the sound of a heartbeat. This is the sound of death approaching.

"Whew!" Yan Maolin took a deep breath, pulled up Li Xu and ran wildly. If the white trajectory is a nuclear bomb, Nanjing will definitely eat a few. Now you have to find your parents away from the city.

"Xiao Su, nuclear war has broken out!"

"What? Nuclear war ......" Li Xu almost fell down with a weak leg, and was dragged forward by Xiaolin.

"Mom and Dad, nuclear war has broken out. Drive to the suburbs! Yan Maolin took out his mobile phone and dialed the phone and shouted loudly.

At this time, the crowd on the street is scattered, and the large electronic screen on the street plays the evacuation message on a loop.

Some people simply gave up trying to survive and cried on the street, constantly calling for their mother.

Someone took the opportunity to rob the supermarket in order to survive the apocalypse.

Some people even looked around for bottle caps, thinking that the last days would use bottle caps as currency, so that they could make a fortune.

At this time, five nuclear bombs rushed towards the city of Nanjing according to the established route.

Yan Maolin found a shared bicycle, held Li Xu in his arms, and frantically pedaled the bicycle in the direction of home.

"Brother, are we all going to die?" Li Xu leaned tightly into his brother's arms, and there was only a sense of security in the world.

"No, no, we'll all be fine, believe brother." Yan Maolin was flustered in his heart, but for the sake of Xiao Su, he had to pretend to be strong.

Cars on the highway are fighting for the way out of the city, only to be blocked in the city, and people get out of the car and flee outside the city. Air raid sirens sounded throughout the city, the sounds of help were endless, and the voices of despair were all around. As the minutes passed, they got closer and closer to death.

"Hurry, hurry!" Yan Maolin's sweat flowed down his cheeks, and his heart became more and more anxious.

Feeling the sweat falling on the back of her neck, Li Xu turned around and saw her brother sweating profusely, she understood that if this continued, neither of them would be able to escape. She used to be so cowardly, but at this moment, she seemed to have made up her mind, turned around and put the note into Yan Maolin's arms, stood up and approached Yan Maolin's ear.

"Brother, you have to live well, I, I like you." Li Xu jumped off the bike with tears in his eyes.

The car suddenly became lighter, and the speed of the car became much faster, and at the same time, Yan Maolin suddenly lacked something in his heart.

"No!" Yan Maolin stopped his bicycle urgently, looked back, and saw Li Xu who was rolling on the ground and hurting himself. Perhaps the desire to survive can make the right choice and save at least one person. But there are some things, some people are more important than life, and if you lose her, then what's the point of living.

Without thinking much about it, Yan Maolin immediately rode back, picked up the scarred Li Su, and stroked the wound on her face in distress.

"Fool, how can I live without you." Yan Maolin hugged Li Xu deeply in his arms, as if he never wanted to be separated.

One of the nuclear bombs rushed towards the place where Yan Maolin and Li Su were, and as the distance approached, the nuclear bomb automatically turned on the safety.

Time seemed to stand still, and the running bodies of Yan Maolin and Li Xu were frozen.

The nuclear bomb reached 5 meters above the two men between electric sparks. The nuclear trigger is pulled, a neutron bombards a uranium-235 nucleus, and the chain reaction unfolds. The instantaneous release of a large amount of energy distorts the space.

The light released in an instant evaporated the entire street, and the space where Li Xu and Yan Maolin were located was torn apart by a huge amount of energy, Yan Maolin and Li Xu's bodies were swallowed up and disappeared by the cracks, while the others were directly vaporized by the high temperature decomposition into an atomic state. Five nuclear bombs wiped the city of Nanjing off the face of the earth.

Around the world, the crystallization of human civilization has been uprooted in New York, San Francisco, Washington, Beijing, Shanghai, Tokyo, New Delhi, Moscow, Paris, London, Berlin, and so on. This layer of bacteria on the earth is eventually destroyed by itself.

The nuclear explosion first emitted a huge amount of radiation that vaporized all living things within a radius of several kilometers. The radiated shock wave then spreads at the speed of sound, destroying the structures encountered. Finally, there are radioactive fallouts and radioactive rain, and once people come into contact with it, they will get radiation sickness and gradually die.

A nuclear explosion sends a large amount of dust into the air, which absorbs sunlight and makes the ground night. The high temperatures produced by a nuclear explosion produce large amounts of nitrogen oxides, which can react with ozone and destroy the ozone layer.

The global cooling of the global temperature caused by the dust covering, and the ice sheets of the Arctic and Antarctic gradually extended towards the equator. Heavy snow falls on the equator, where there is no snow all year round, and the temperature remains at minus 20 degrees Celsius. A large number of creatures froze to death, including surviving humans in the equatorial region. The ice age, originally 3,000 years later, came earlier. Ice caps also form in the equatorial seas, and the Earth is completely covered with snow and ice after 3 months. The formation of the land ice sheet has caused a large amount of fresh water to be transferred from the ocean to the land ice sheet, and the global sea level has dropped by 100~200 meters. Coastlines are altered, and organisms in shallow sea areas are forced to be exposed to the air, causing a large number of shallow sea organisms to die.

The dust caused the eternal night, and under the secondary impact of the ice sheet, the land green plants and marine photosynthetic organisms died in large numbers, leaving only dormant spores and seeds to retain hope. The disappearance of photosynthetic organisms deprives the atmosphere of its source of oxygen, and the remaining oxygen is respirated by aerobic organisms. The oxygen level in the atmosphere gradually approached zero, and another death came. This time, only a handful of the few hundred people who survived relied on electrolysis of water to produce oxygen survived.

When snow falls around the world, gray dust snowflakes also fall. Radiation fallout greatly increases the probability of genetic mutation in organisms, and fungal bacteria rely on high reproduction rates to turn high genetic mutation rates into advantages, which in turn accelerates their evolution. The superfungus is the final blow to the surviving humans on the surface, and the giant slime molds search for the surviving humans in the city and wrap them up and digest them. Superbugs and viruses are everywhere, and epidemics spread across species.

A year later, there are a large number of fungi scattered on the ground, and these creatures constitute the last bit of life on the earth. Only astronauts and space tourists in space are left alive.

A year later, the dust cleared. With no ozone layer to protect beyond the equator, lethal ultraviolet rays return to the earth, ruthlessly killing the last remaining fungi on the ground. Huge forests of mushrooms and fungi turn to black water in the intense sunlight.

Before the formation of the ozone layer, there was no life on land, and only the ocean could block these deadly ultraviolet rays. 2.6 billion years ago, photosynthetic bacteria released large amounts of oxygen. This oxygen forms an ozone layer at high altitudes, which acts like a sun umbrella to filter out harmful ultraviolet rays. Provide security for the subsequent biological landing.

The nuclear explosion caused the hole in the ozone layer to expand to the equator, and the original protective umbrella disappeared. The land is back 2.6 billion years ago. About 85% of all living things died in this event, which is the sixth mass extinction.