Fifteen kilometers away.

Standing in the middle of the white snowfield, the steel platform looks a little bit like the creation of this era—the neatly packed bare structure, the beams and steel cables hung with ice picks, and the barbed wire fence all reveal the beauty of the industry.

Hundreds of people were busy around it, making preparations for the detonation.

Since the whole principle device weighed nearly ten tons, and the hummingbird went to the front again, it was not possible to carry out the final assembly in Neverwinter, so the parts could only be assigned and dragged to the test site and assembled on the spot.

Fortunately, its structure itself is very simple, and the design has considered the need for split transportation, so the requirements for workers are not too high.

This is what sets Sunlight apart from other weapons - even if the venue and equipment are already set up, it still takes a day or two to complete the final preparations.

At this moment, Roland and Anna are standing at the top of the tower, directing the assembly of the device.

"Next is the No. 3 core component, pay attention to the direction of the interface, be careful of bumps!"

"Everybody listen to me!Three, two, one!"

With the call of the Captain of the Workers, a silvery-white cylinder was slowly pushed into the device.

It wasn't until this step was completed that Roland slowly breathed a sigh of relief.

The cylinder contained the main source of energy for the test explosion - two separate pieces of uranium-235 cylinders, each of which had a mass of 20 kilograms. When the two are combined, a total mass of forty kilograms of charge will be provided. This value is below the critical limit of 53 kilograms, and theoretically there will be no violent fission reaction, but as he said before, the critical value is not a fixed value.

Shape, temperature, pressure, and other conditions can cause this value to change, which is why "nuclear weapons" that rely purely on stacked materials have little actual combat value. For example, 52 kilograms of uranium-235 in the sphere state seems to be stable, but it is actually a volcano that is ready to erupt. Even the slightest impact or vibration can cause it to cross the critical line.

Similarly, the use of multiple small uranium blocks, while safe, can also make detonation exponentially more difficult - when several uranium blocks are combined, the whole can indeed exceed the critical point, the high temperature generated by the fission reaction will cause the uranium block to expand rapidly, reducing its density in disguise, and the violent explosion will push the raw material away from it, thus interrupting the reaction.

All in all, a reasonable configuration must not only make uranium critical, but also maintain it in this state for as long as possible in order to exert the power of the fission reaction.

The gun configuration is called a gun because its principle is very similar to that of the ancient musket, in which one uranium block is violently pushed against another by the detonation of explosives. Under enormous pressure, the density of the uranium block increases rapidly, and even a slightly lower mass can cross the critical point.

Once the device's casing was attached, Anna hand-inserted a can of encapsulation coated with a radioactive source warning sign into the reserved tail connector.

That was the last key component of the test explosion.

For a moment, Roland felt as if he had been pricked in the face, and he even paused for half a beat to breathe.

Polonium-Beryllium Neutron Source.

As the name suggests, it provides a large number of free neutrons for fission and is the most direct way to reduce the critical value. Inside the can-like metal container were a row of hollow balls—each the size of a ping-pong ball, with a marble-like polonium ball at its core, tightly wrapped in gold leaf, and surrounded by a circle of honeycomb-shaped beryllium sheets.

When the uranium blocks collide, they will also smash the small jar located at the bottom of the "barrel", and all the hollow balls will be pressed thinner than paper by the violent explosive gas, and after the gold leaf is broken, the beryllium pieces will be intimately attached to the polonium balls, and the alpha particles released by the latter will be fully accepted, and then several times the neutrons will be ejected.

These neutrons will participate in the fission reaction of uranium-235, and if you are lucky, you can consume a few more percent of the raw material before the reaction is terminated, greatly increasing the power of nuclear weapons.

Since Polonium-210 has a half-life of only 138 days, providing a replacement interface is an essential design. It is also extremely dangerous to leave the neutron source in the weapon for a long time, after all, polonium and beryllium can spontaneously emit neutrons when they come into contact, and if the gold leaf is damaged, the consequences are unimaginable.

Once the Polonium Beryllium Neutron Source is loaded into the Principle Device, it goes from being a gentle and harmless thing to a monster that threatens to engulf everyone on the scene at any moment.

Although Roland knew that his feelings were only illusions, and it was impossible for people to capture the changes in the number of neutrons in the environment, his breathing was still much lighter.

At this point, the principle device can be considered to have officially completed all the preparatory work before detonation.

Anna took the initiative to take his hand.

"Give the order. ”

In the other party's calm and calm gaze, Roland nodded slightly.

Regardless of the outcome, Project Sunlight has finally come to this point.

And after this step is taken, humanity will go to a new realm.

He looked at the guard Sean, "Pass my order, notify the command post, and count down to the six-hour ignition!"

"Yes, Your Majesty!"

「6:00」

"Woo————— woo————— woo————— woo——————"

"Device 1 has entered the ignition stage, repeat, the No. 1 device has entered the ignition stage, please pack up immediately and leave the site in an orderly manner according to the drill plan! Note that this is not a drill, the test site will be closed in an hour, everyone must evacuate to a safe place before this!"

Soon, the evacuation notice sounded along with the sound of the siren.

"Hurry up, let's gather in the open space in front of the tower, don't pull down the next person!"

"The second construction team reported the number, one, two, three ......"

"The gate of the test explosion station is blocked!"

"All members of the Witch Squad have arrived and begun to lead the team to evacuate. ”

The quiet snowfield seemed to boil, and the shouts of the people and the repeated sirens reflected each other, and the atmosphere became tense and solemn for a while. Everyone knew in their hearts that they were about to witness an unprecedented trial.

「3:00」

At the command post, Roland and Anna took out two keys and opened the console cover together.

When the switches are pressed one by one, the green lights on the countertop also turn on in turn.

"The main cable is being powered!"

"The first day of the mystery moon is working normally, and the load is steadily rising. ”

"Now switch to line one. ”

"Understand, the line has been connected, and the power supply of the principle device is normal!"

The observer reported loudly the operation of the initiation system, until the last green light came on, indicating that the current had been transmitted to the elevated platform fifteen kilometers away through multiple boosts.

「1:00」

The alarm was also sounded over the command post, which meant that there was only one hour left for the detonation procedure.

The doors and windows of the bunker were all closed, and the oil lamps were extinguished one by one to avoid accidents caused by vibration.

The upper echelons of Neverwinter entered a dedicated observation room, and according to Roland's instructions, its façade was built into a trapezoidal shape to better resist the shock wave, while the inner end was deepened to accommodate the massive body of the original carrier.

Pasha and the Tachira Witches have been waiting for a long time.

「0:15」

It's getting dark.

The last hurried sirens finally arrived.

Whether it is the high-level officials, soldiers or workers, they all wear black sunglasses to protect against the bright light according to the content of the previous drill.

Although most people don't understand why they still wear such glasses that obstruct their vision on this dark and snowy day.

It's not like you can't see anything.

「0:05」

"Countdown, five minutes!"

When the announcement sounded again, the scene had become silent.

All communication and discussion had stopped, and everyone stared intently at the pitch black ahead, involuntarily holding their breath.

"Three-minute countdown!"

Roland felt a fine sweat in his palms.

Anna looked at him with a smile and gently took him.

"Countdown to the minute!"

On the other side, a hand reached out, and then five fingers were folded.

"Ten seconds countdown!"

"Nine!"

Although it was a pity that he couldn't press the detonation button himself, Roland knew that this long road of historical facts had just begun.

"Three!"

"Two!"

"One!"

"Detonate!"

The snowfields in the distance were silent, as if nothing had happened—time seemed to freeze in this moment, as if a long time had passed, and as if it had only been a brief moment.

Then an extremely dazzling blue light burst out from the horizon, tearing apart the darkness in front of him in an instant!