"Then please come and explain it to everyone in detail."

After the commander finished speaking, Klein walked among the students and made an invitation gesture to Arthur. Arthur hesitated for half a second, then looked at Klein and nodded.

He walked towards the wall, then turned around, his slender body casting a long shadow on the wall.

The shadow overlaps with the weapon on the screen, making it look like a pair of chopsticks.

"If I'm not wrong, this weapon is a weapon that only exists in the theoretical stage, and it is more destructive than any weapon we can imagine.

Its lethality far exceeds that of the hydrogen bomb. The lethality of the hydrogen bomb is mainly reflected in the ultra-high temperature, shock wave, optical radiation, electromagnetic pulse and nuclear radiation generated by the explosion. However, most of its power is instantaneous. Although the explosion is powerful

, but the nuclear radiation produced is weak and the subsequent lethality is insufficient;

Compared with atomic bombs, atomic bomb explosions mainly use uranium 235 or plutonium 239 as fuel. After the explosion, a variety of radionuclides are produced, such as iodine 131, which has a half-life of 9 days, and cesium 137, which has a half-life of 30 years. The area covered by the shock wave of the atomic bomb is

There was a fatal threat within a month, but fortunately, the explosion pushed these particles into the air and spread them further, and the radioactive materials were diluted, so that these particles alone had almost no lethality.

But the cobalt bomb is different. Its main part is a neutron bomb, a low-mass tactical hydrogen bomb that uses high-energy neutron radiation as its main lethality. Its purpose is to kill enemy personnel and cause relatively little damage to buildings and facilities.

It is an imaginary salt bomb with a special "radioactive fallout" design after detonation, that is, "atomic dust", which is the radioactive dust that falls from the sky after a nuclear bomb explodes or a nuclear reactor leaks, and the cobalt 59 shell wrapped around the hydrogen bomb.

After the detonation, the neutrons produced were absorbed by cobalt-59 and turned into the radioactive isotope cobalt-60, which then fell back to the earth in the form of radioactive dust.

It contains a large amount of radioactive elements, which is a kind of radioactive pollution. Contamination of animal skin can cause skin β-ray damage, which can lead to contamination of the entire food chain.

The most terrifying thing is that it can last for more than a hundred years, and even escaping underground may not be able to avoid radioactive contamination."

After Arthur said this, his flight suit was almost soaked through. His back was cold, his hands were trembling slightly, and fear had spread throughout the training ground along with his words.

"Very good, thank you, Mr. Arthur, for your explanation. That's what happened. He is almost right." The commander paused for a moment and continued: "This is the reason why the earth is what it is now, although it is not the direct reason."

Students who heard these words for the first time all expressed surprise and grief at not knowing what to say.

No matter when, no matter how far human beings fly into the starry sky, the loss of the earth will be an eternal pain for all human beings.

At this moment, this scar was mercilessly uncovered, and it burned everyone's heart coldly.

Klein tried to comfort the students in the training ground, but with little effect.

"What is the truth?"

Suzaku remained calm at this time, but the commander obviously hadn't made his words clear yet. Suzaku had a short temper and didn't like procrastination.

"Let's continue watching the next video." The commander's voice appeared and then disappeared.

The screen turns black and then brightens.

This time, what appears on the screen is a small spacecraft. The spacecraft is docked at the Mars launch station, and the Carthage-11 launch vehicle is quietly waiting for all preparations before liftoff.

Then, the two astronauts waved to everyone in the screen, and the next second, the spacecraft was already on its way to the earth.

"Carthage, Carthage, this is Lake Baikal, everything goes well, we will arrive on Earth at the scheduled time."

"You have more than a hundred days to get along day and night. It feels good to fall in love in space."

"Then I have to ask Miranda if she is willing."

"I'm not interested in a blond bad boy like you. Hurry up and complete the mission. I will miss Mars."

The communication sound ends——

At the end of the picture, there are desperate cries.

"Carthage, Carthage, call Carthage and request an automatic return."

"The request is approved, please switch to the automatic return to home procedure. The operation manual is on the right side of the navigation console. Note that you only have one chance to switch to the return to home procedure."

Sizzling——

"Hell, I lost Miranda."

"Failed to start return home procedure!"

"Warning, the return procedure failed to start!"

"Warning, the return procedure failed to start!"

The man's crazy voice filled the entire training ground. Later, Arthur would always think of this voice, which contained all the fragility and helplessness of the human species.

It reminds Arthur that no matter when human beings face the power of the universe, they will always remain ignorant of persistence and unhesitating simplicity.

This is probably the only spiritual core that human beings have that can face the past, present and future.

The picture gradually stops, as if time is frozen on the wall.

A white circular aircraft slowly turned over in the deep black space, falling towards a distant gravitational force.

That should be Earth.

The commander's face appeared on the screen again, calm but tired.

"This is a two-stage spacecraft. You should have learned about this kind of spacecraft in recent training."

"Yes, Commander." Klein said truthfully, "These students are all better than we expected."

"Excellent! The efforts of Professor Klein and Mir are remembered by the entire United Citizens."

What the commander said——

It's a bit exaggerated.

All the students below thought this way.

The more powerful the praise, the more difficult the task. Ann and Jacob looked at each other, then at Suzaku, and finally walked to Arthur and asked: "Squad leader, why do I feel something is not good?"

"Let's see how to say it first."

At Arthur's suggestion, Ann and Jacob, who had been silent, quieted down.

“Professor Klein is just like you, he doesn’t know what the purpose of restarting the [World Heritage List] plan is, and now he will work with you to understand part of it.

Please return your attention to the two-stage spacecraft. This spacecraft is the first spacecraft of the [World Heritage List] project. It was launched earlier than your parents were born. The purpose is to investigate and find the [World Heritage List].

】The secret hidden in

The dust principle caused a chain explosion. Finally, the experiment went out of control, leading to the mass extinction of life. Human beings cannot survive in such an air environment. This is the main reason for our comprehensive immigration to Mars.

This disaster is tragic and is the revenge of arrogant science. We paid a huge price, but we also realize that the huge effect of this explosion is an extremely precious energy, so we plan to return to Earth.

Find out how it is made.

The Baikal went to Earth for this purpose, and the two-stage design ensured that when it entered the atmosphere, violent combustion would not destroy the entire mission. I think you have all learned about this in relevant courses."

"Double insurance strategy." Li Xiang said.
Chapter completed!