I live in the Martian wilderness!

"bite--"

[Report from the Colonel: The Shenggong module has completed the printing of all carbon-sulfur composite boards. The discharge port has been unlocked.]

Gu Yu glanced at the time; it was 11 a.m. He passed through the Oasis One airlock and arrived at the Sky Shuttle.

The finished product compartment cover on the side of the Shen Gong module slowly slid open, revealing forty freshly baked boards neatly stacked on the tray.

They are entirely a deep, matte black, the natural color of toner.

However, under the refraction of weak sunlight, the surface also has a waxy yellow luster, which is the unique texture after sulfur seeps into the carbon micropores as a binder.

This material is lightweight and tough. Although it cannot withstand high temperatures, it is the perfect structural component in the low-temperature environment of Mars.

Without any hesitation, Gu Yu immediately issued a new order: "Very good. Xuan, clean the printheads immediately and switch the feed system."

"I filled in the basalt powder and preheated the microwave generator to 1100 degrees Celsius. While I was assembling the pool, I immediately started firing the bricks!"

"Command confirmed. High-temperature sintering program loaded... Preheating initiated."

As the internal fan speed of the Tissot suddenly increased, the tireless Tissot engineering vehicle roared once again, accumulating power for the upcoming high-temperature forging.

The backyard is currently in a vacuum state. If the back door of the shelter is opened directly to move materials, the precious air will be instantly leaked away.

The only way is to use the engineering ramp 1.5 kilometers away to take the outer route.

"Xuan, activate the Mars rover and drive it next to the shuttle. This time, I'm going to use it like a pickup truck."

Gu Yu began to move the still-warm boards one by one into the spacious trunk of the Xuntian.

Then I sat in the cockpit of the Sky Surveyer and fastened my seatbelt.

With a soft hum of its motor, the Sky-Covered Destroyer, laden with building materials, kicked up a cloud of dust and sped toward the cave entrance 1.5 kilometers away.

As the high-power LED searchlights on the front of the vehicle were turned on, two beams of light instantly pierced the darkness, illuminating the wide lava pipe.

This is a vacuum ice cellar at -65 degrees Celsius, and also Gu Yu's future backyard.

"Arrived at the designated construction site."

Gu Yu stopped the car and looked at the basalt ground that had been flattened and compacted by the Tian Shuo.

It is about 5 meters away from the back door airlock of the shelter, and the ground is extremely flat, making it an ideal location to place the "runway pool".

Gu Yu jumped out of the car, opened the trunk, and started working.

In the low gravity environment of Mars (0.38G), those already lightweight "carbon-sulfur composite panels" are as easy to move as foam plastic.

He unloaded the forty boards onto the ground and arranged them neatly by type: base plates, side wall plates, and curved guide plates.

"Xuan, project the 'runway pool' assembly blueprint."

"Understood, Lieutenant Colonel. AR guidance activated."

In Gu Yu's field of vision, a blue light frame made of dotted lines immediately appeared, covering the open ground in front of him.

This is a standard "racetrack-type photobioreactor" structure.

Just like a running track on a playground, it consists of two long straight lines with semicircles at both ends, and a long partition in the middle to guide the water flow in circulation.

Gu Yu picked up a base plate and placed it at the starting position of the blue light frame.

The edges of these boards are designed with a precise "groove" structure to ensure physical positioning during splicing.

However, the card slot alone cannot guarantee that there will be no leaks in this environment with huge temperature differences.

Gu Yu took out a tool that looked like a pistol from his toolbox—a handheld induction heating welding gun.

Xuanjian pointed out from the side, "Lieutenant Colonel, the melting point of sulfur is 115 degrees Celsius. In a vacuum, the viscosity of liquid sulfur changes drastically with temperature."

"We recommend that you lock the heating gun temperature at 140 degrees Celsius. This is the golden range where sulfur has the best fluidity and will not damage the carbon skeleton."

"receive."

Gu Yu knelt on the ground, aligned the groove of the second base plate with the groove of the first plate, and clamped it tightly.

Then, I pulled the trigger of the welding gun and slowly slid the flat heating head along the seam between the two boards.

A wonderful chemical reaction occurred.

There was no open flame, but under the influence of high-frequency electromagnetic induction, the sulfur-rich surface layer at the joint of the board melted instantly.

A trail of golden, viscous liquid sulfur seeped from the edge of the originally hard black board.

They flowed and merged between the two boards, filling every microscopic pore.

Gu Yu quickly moved the heating gun away.

Under the "quenching" effect of the surrounding ambient temperature of minus sixty degrees Celsius, the golden liquid sulfur turned back into a hard solid in just a few seconds.

The two boards were thus firmly "welded" together at the molecular level.

"Sizzle—sizzle—"

In the silent underground pipes, the only sound was the faint vibration of current flowing through the coil.

Gu Yu, like a focused tailor, used a hot gun to stitch together pieces of black board.

First, the base plate was laid out. The 15-square-meter black platform, like a huge black mirror, was laid flat on the rock.

Next are the side walls.

Gu Yu inserted the 30-centimeter-high side baffle vertically into the slot of the base plate and then heated it again to weld it.

Finally, there are the middle baffle and the curved plates at both ends.

As the last golden sulfur crevice cooled and turned black, a black running track pool, 5 meters long and 3 meters wide, appeared prominently under the beam of the searchlight.

Gu Yu stood up, circled the masterpiece, and kicked the side wall with his foot.

"Thump!"

A dull echo came from the sole of the boot, without moving an inch.

"The structural strength is perfect," Xuanjian commented. "This seamless welding process is sufficient to withstand the lateral pressure when fully loaded with water."

"First one done. Now, put together that 5-square-meter breeding pond, and today's puzzle game will be complete."

With the experience gained from the large pond, assembling this 5-square-meter breeding pond was a breeze.

In less than forty minutes, a miniature black running track pool nestled next to the large pool.

Two black geometric shapes exude an industrial beauty under the searchlight, as if they were the earliest remnants of civilization on this planet.

"Lieutenant Colonel," Xuan Jian's voice suddenly rang out, "Although the structure is complete, according to thermodynamic simulations, the system is currently missing an active water temperature control system."

Gu Yu was taken aback: "Water temperature control? Aren't we going to heat the entire ecosystem to 25 degrees Celsius later?"

"The data does not support this plan, Lieutenant Colonel." Xuanjian immediately projected a thermodynamic chart onto the HUD.

"First, the evaporative cooling effect. The track pool is an open water surface, and the evaporation of water will continuously take away heat."

"According to calculations, even if the air temperature remains constant at 25 degrees Celsius, the water temperature can only be maintained at around 20 degrees Celsius without active heating."

"Second, the production threshold. Spirulina can only survive at a water temperature of 20 degrees Celsius; but at a water temperature of 32 degrees Celsius, they will grow rapidly. There is a huge gap of 30% in daily production between these two."

Xuanjian projected several red virtual lights and shadows at the bottom of the pool: "Therefore, I strongly suggest installing submersible electric heaters at the bottom of the pool to lock the water temperature at the golden line of 32 degrees Celsius."

After listening, Gu Yu said, "I understand, Xuan. You mean to use the Divine Craftsmanship Module to print a few more miniature heating rods, just like the one down in the well, only with the power adjusted to 5 kilowatts?"

"Yes, Captain."

Gu Yu nodded. "Okay, once the wall is built, we'll build this immersion heater."

[You have been added to the production queue.]

Having finalized the follow-up plan, Gu Yu glanced at the time, then crawled back into the cockpit of the Sky Patrol, closed his eyes to rest, and quietly awaited the completion of another "major project."

……