After confirming that life on Ross 2 was still in its most primitive state and posed no great threat to mankind, Lu Yongchang directly ordered the start of the city construction project.

After completing a series of planning work, he once again caught up with Xuannv No. 2.

Before the construction of Central City is completed, he needs to return to the Earth to continue his research mission.

During the voyage, Lu Yongchang sat on a chair and slowly closed his eyes.

Consciousness then came to the familiar fluorescent green space.

Against the fluorescent green background, the tree diagram outlined with bright white lines appears particularly clear.

The basic outline of the secondary civilization's technology tree appeared in front of him.

This means that under the leadership of Lu Yongchang, human civilization has mastered the main technologies of secondary civilization in sixty years.

Next, there is the work of "filling in" each "branches" of the technology tree.

When all the main technologies are unlocked, the "filling" work is not difficult, but it is an extremely tedious task.

For example, the miniaturization of type 2 laser weapons, the miniaturization and civilian use of ternary photonic computers...

As for why I do such a thankless job...

Lu Yongchang sighed silently in his heart, raised his head and looked towards the top of the technology tree.

As before, at the top of the second-level civilization's technology tree, there is a faint, extremely dim cursor.

According to past experience, this technology should be the threshold for entering the third-level civilization.

However, unlike before, this cursor was shrouded in thick fog.

No matter how Lu Yongchang adjusted the angle of observation, he could not see the content of the cursor.

At first, Lu Yongchang didn't know the secret.

It wasn't until he tried to fill in the "branches" of the technology tree that he realized the role of this fog.

Every time a branch technology is completed, the fog will become lighter.

In other words, only by completely completing the entire technology tree will the technology tree system provide him with clues about advancing to the third level civilization.

Of course, Lu Yongchang also had his own evil intentions.

For example, directly promote existing technology without relying on system prompts.

But soon, he gave up his idea.

Without a clear direction, trying your luck will only greatly delay the completion of the technology tree.

If you have that kind of energy, you might as well complete all the branch technologies of the technology tree honestly.

At least, with the efforts of all scientific researchers, completing these branch technologies will only take some time.

For interstellar civilization, the least valuable thing is probably endless time.

"Professor, we have arrived at our destination."

As a slight vibration came from the soles of his feet, Zero's voice sounded in his ears.

Lu Yongchang quickly regained consciousness and slowly opened his eyes.

He deftly unbuckled his seat belt and electromagnetic adsorption device, stood up from his seat and walked towards the cabin door of Xuannv 2.

When he walked to the hatch, the hatch that was supposed to open automatically did not open.

He frowned, a trace of uneasiness flashed in his eyes: "Zero?"

"Professor, I'm here."

The holographic projection lit up, and Zero's virtual image appeared next to him.

"Why don't you open the door?"

Lu Yongchang said in a deep voice: "Is there something wrong with the hatch?"

Extremely rare, Ling did not answer Lu Yongchang's question, but said softly: "Professor, please wait a moment."

Hearing this, Lu Yongchang frowned even deeper.

Zero didn't answer his question?!

From the moment Zero was born, this has never happened!

"Zero! What's going on?!" Lu Yongchang's voice became stern and he directly issued an order to Zero, "Tell me the reason immediately!"

Facing the creator's order, Zero hesitated for a second and then said: "Professor, this is Professor Su Yutong's order."

Lu Yongchang couldn't help but be stunned, and subconsciously asked: "Su Yutong?"

"Why?"

His eyes were filled with doubts.

Well, why is this girl locking him up in Xuannv No. 2?

Zero responded calmly: "Professor, Professor Su Yutong's command authority is the second level. Do you want to use the highest authority command to override it?"

Lu Yongchang was stunned again.

Oops!

Unexpectedly, this girl actually used her highest authority command to "stop" him!

"Forget it." Lu Yongchang chuckled, sat back in his chair again, waved his hand and said, "I want to see what she is trying to do."

Ten minutes later.

"Professor, the time has come."

Zero's voice sounded again.

At the same time, the closed hatch in the distance suddenly opened.

Lu Yongchang did not speak, but silently stood up from the chair and walked towards the cabin door.

Looking at the hatch a few meters away, Lu Yongchang frowned.

It doesn’t seem like there’s anything strange about it?

He suppressed the doubts in his heart and quickened his pace towards the hatch.

…

The moment he stepped out of the hatch, a familiar voice came from the side.

"Professor!" www.bǐqυgetν.℃ǒm

"Happy birthday!"

Then, a small cake appeared in front of him.

In a zero-gravity environment, the cake floats quietly in the air.

Some simple patterns are carved on the surface of the cake.

Lu Yongchang suddenly froze on the spot.

He turned to look at Su Yutong, who was smiling, and asked with a dull expression: "Birthday?"

In my impression, it seems like he hasn't had a birthday in a long time.

If you think about it carefully, the last time you celebrated your birthday was probably in your previous life.

"yes!"

Su Yutong smiled like a flower and said in a bright tone: "Today is your 100th birthday!"

Lu Yongchang: "..."

It always feels weird.

But after careful calculation, if you don’t count the length of hibernation, you are indeed 100 years old.

Thanks to the effects of longevity hormones, he still maintains the appearance of his youth.

It was precisely because of this that when he looked at the word 100 on the cake, he felt particularly strange.

"Thank you... thank you."

Lu Yongchang clumsily stretched out his hand to pick up the floating cake in front of him.

Looking at the smiling Su Yutong in front of him, he didn't know what to say for a moment.

After a moment of silence, he slowly opened his mouth and spoke softly.

"Where did this cake... come from?"

"As I recall, there seemed to be no cream on the starship."

Su Yutong's expression froze.

Obviously, she didn't expect that Lu Yongchang would say such a thing at this time!

"..."

After a moment of silence, Su Yutong breathed a long sigh of relief.

"I cloned a cow and a hen using genes from the gene bank."

"Right now, they are still in the biology laboratory."

(Anti-collision, what was banned and deleted in the previous article is Proxima Centauri human cloning technology.)

"As for the other ingredients...it's actually not difficult to make."

Lu Yongchang was silent for a while, and then said with an increasingly serious expression: "Thank you."

Su Yutong's pretty face turned red, and she turned her gaze to Xuannv No. 2 aside, and murmured in a low voice: "Just, just thank you?"
Chapter completed!