Cataclysmic Era: I can unlock the tech tree

He Bilin silently followed in Tao Yuda's footsteps.

Is the gap really that big?

He Bilin recalled his last experience in a holographic cinema.

I vaguely remember that before entering the holographic theater, there was a label indicating the so-called level of realism.

Among all the simulated scenarios, the simulation of the Earth's environment has the highest degree of realism.

95%.

This is why He Bilin chose to experience it.

only……

Looking back now, although the scenery I saw was incredibly stunning, I still have an indescribable feeling about it.

Perhaps this is the breath of freedom that Academician Tao was talking about?

How can such a 5% difference reveal such complex differences?

He Bilin suppressed his doubts and turned to look into the distance.

The main port of the Earth was open, and the Mysterious Maiden II ships slowly sailed into the endless deep space outside the port.

Directly opposite the port is a planet that is entirely yellowish-brown.

That was their destination—Ross 2, humanity's new home.

……

Ross II.

Central City.

Lu Yongchang sat in his office, watching the outdoor projection screen with satisfaction.

Long streaks of rainbows streak across the azure sky.

Each rainbow represents a Xuan Nu II.

After 242 years of turmoil, struggle, and war, human civilization has finally once again found a stable and peaceful environment for development...

"Beep—beep—beep!!"

A piercing alarm sounded in his office.

In an instant, the brightly lit office was covered in a blood-red stain!

The next moment, a holographic projection appeared in front of Lü Yongchang!

【warn! 】

[Unidentified signal detected!]

[Signal source: Ross154]

Signal frequency: 1420 MHz

【…】

In the blood-red holographic projection, the black lettering appeared particularly shocking.

Lu Yongchang's relaxed mood vanished instantly.

He jumped up from his chair, his eyes filled with horror!

A communication frequency of 1420 MHz!

It has always been the signal band for humanity to search for information about extraterrestrial civilizations!

the reason is simple.

1420 MHz is the frequency of the 21 cm line, a famous spectral line emitted by neutral hydrogen atoms.

As the most common and abundant element in the universe, every advanced civilization that has developed to a certain level will be extremely familiar with this property.

On the other hand, 1420 MHz is a relatively quiet area for radio signals.

In this signal frequency band, the intensity of various background radiations is almost at its minimum.

Therefore, 1420 MHz is an excellent signal frequency choice if one wants to ensure that the signal it emits is not drowned out by the noise of celestial radiation and can be received by advanced civilizations that have developed to a certain level.

And now!

A signal at this frequency was received from the direction of Ross 154!

What this means is self-evident.

Recalling the unusually bright phenomenon from over sixty years ago...

At that moment, Lü Yongchang felt his whole body tremble and a chill run down his spine!

"zero!"

Without almost any hesitation, Lü Yongchang issued the order: "Stop all work!"

"Notify Zhao Zijie, the human fleet is on high alert!"

"All troops, immediately enter radio silence!"

……

Earth

port.

As a piercing alarm sounded on the public communications channel, the open port in the distance slowly closed.

At the same time, the eerie blue flames at the tails of several Xuan Nu II ships that were preparing for takeoff quickly went out.

One by one, red warning lights began to flash.

"W-what happened?"

He Bilin, who was born after the Battle of Proxima Centauri, was stunned for a moment.

Lacking the necessary experience, his brain paused for a moment before arriving at the answer.

It seems... the fleet is in danger?

"How close are we!"

As a familiar voice rang out in the team's communication channel, a tremendous force struck from the side.

Even with the electromagnetic boots helping to stabilize his body, he was still pulled off a stumble by the force.

He managed to steady himself, and after attaching the electromagnetic boots to the ground again, he turned his head to look to the side.

"Academician Tao?"

Upon seeing familiar faces, He Bilin's panic subsided somewhat, and he asked urgently, "Academician Tao, what exactly happened?"

Why...?

Tao Yuda's expression was extremely serious, with no smile on his face.

"This is……"

"Level One Combat Readiness Alert"

"Usually, it only rings when encountering other civilizations!"

Hearing the sound coming from the headphones, He Bilin subconsciously held his breath.

As Tao Yuda finished speaking, a series of huge holographic projections unfolded in the air.

【warning】

[Signal from an unknown civilization detected]

[The entire ship is on Level 1 combat readiness.]

Unlike Tao Yuda, a seasoned veteran, he had never experienced anything like this since birth.

"Then... what should we do?"

Thinking of the Battle of Proxima Centauri recorded in historical documents, his voice trembled slightly as he asked in a low voice, "What should we do?"

Tao Yuda turned around and walked quickly toward the command center.

"Commander Zhao Zijie is still on Earth. Let's go to the command center."

After a brief pause, Tao Yuda's voice rang out again.

This time, his voice was filled with solemnity and helplessness.

"Get ready."

"Human beings' peaceful life may be coming to an end before it has even begun."

……

Earth

Next to the command center is a room that serves as Zhao Zijie's office and rest area.

As the overall tactical commander of the human fleet, Zhao Zijie did not go to the central city with Lü Yongchang.

He remained on the Earth.

Even compared to Central City, the quality of life on a starship is several levels lower.

This is to prevent all sorts of unexpected situations from occurring.

Whether it's inside or outside.

As long as the flagship remains and the ternary quantum supercomputing center remains, humanity still has hope of making a comeback.

The moment the 1420 MHz signal arrived, alarms sounded simultaneously in both the office in the city center and this office.

Zhao Zijie's expression changed slightly as he looked at the bright red warning sign in front of him.

Then, he sighed deeply, his eyes revealing a hint of weariness and helplessness.

"Is another war about to begin?"

As he spoke, he untied the electromagnetic adsorption device on the chair.

"Zero, contact Professor Lü..."

Before he could finish speaking, Lü Yongchang's voice came through the loudspeaker.

"...Human fleet, level one combat readiness!"

"All troops, immediately enter radio silence!"

Zhao Zijie didn't say anything and silently walked to the door.

"Zero, initiate wake-up procedure."

"Awaken all personnel on standby."

"also……"

At this point, Zhao Zijie paused.

"All starships and weapon systems are fully unlocked."

"Target, Rose, 154!"