Reborn in 2011, I am the chief designer of aerospace.

But the only truly decisive component on this aircraft is its engine.

In Mars' thin atmosphere, traditional propellers are almost useless, as they cannot effectively grab air to generate thrust. Jet engines are also useless, because the main component of the Martian atmosphere is carbon dioxide, which cannot support combustion.

To solve this deadlock, the "Butterfly" was equipped with a "ramjet-enhanced hybrid rocket engine". The researchers injected liquid oxygen into a combustion chamber filled with high-density rubber and ignited it. The burning rubber itself constituted the rocket's propellant.

However, unlike traditional rockets that directly eject exhaust gas, this "ramjet boosting" technology collects carbon dioxide from the Martian atmosphere during flight and forces it into the exhaust gas flow of the nozzle, thereby greatly enhancing propulsion.

Ultimately, they built this high-powered engine that utilizes the thin Martian atmosphere to "borrow strength from the Martian surface."

Song Xingye is currently inspecting this crucial aircraft. His primary task is to use compressed gas to inflate the fuselage frame and wing spars. Next, he must add liquid oxygen to the engine.

However, the second task was a tricky problem. The Butterfly was designed to use oxygen extracted directly from the Martian atmosphere, which should have been provided by the chemical plant that produced fuel for the return capsule.

Ironically, the fuel plant at the Agamemnon farm was produced in the same batch as the malfunctioning plant that caused the sinking of the Darwin.

Fortunately, the Butterfly was ultimately just an airplane, not a launch vehicle, and the amount of liquid oxygen it required was only one-thousandth of the fuel consumed by the return rocket.

After an emergency consultation, the team of experts on Earth unanimously agreed that since the required amount of liquid oxygen was extremely small, Song Xingye could completely bypass the main atmospheric compression system and the Sabatil reactor, which had fatal hidden dangers, and directly activate the backup electrolysis system and Stirling liquefaction unit.

Recalling the painful lessons learned from the catastrophic failure of the Darwin's sealing system, he decided to adopt the most conservative approach: even if it relied solely on solar power to refuel the tanks drop by drop, he could accumulate enough liquid oxygen in a few weeks at the latest, and no more than a few months at the worst.

So Song Xingye began the long and tedious process, watching as liquid oxygen was injected drop by drop into the aircraft's fuel tank.

……

The wasteland where they were stationed was once the coast of a vast ocean. Mira often pondered how many fossils were buried on this ancient and arid seabed, and to what extent life here had evolved.

Did life on Mars once originate from this ocean, only to eventually perish as the rivers dried up and the planet froze? What caused the evaporation of this ocean and the loss of the entire atmosphere?

During her eight days at Camp Agamemnon, Mira was gradually emerging from the suffocating depression of the past few weeks, as if she had been reborn. For the first three days, she curled up in the dome of her habitat, and then she changed to spending an hour on the Martian surface every day.

She first walked toward the greenhouse module and was surprised to find that this device, which had been abandoned on the harsh surface of Mars for many years, was still intact. During the long years of being unattended, several yucca plants and evergreen shrubs had stubbornly survived inside.

She gently stroked the plants through her gloves, touching their thorny leaf tips.

"You are like me," she murmured to them, "we are all survivors."

After that, she became fascinated with taking solitary walks along that desolate, ancient beach before sunset.

The waves of the ancient ocean have long since disappeared, and the sand on the beach has long since calcified into hard rock layers, but she can still read the rhythm of the waves rising and falling from the solidified texture of the sandstone surface.

She would often find a shallow spot, brush away the dust, and search for solidified salt crystals beneath the chalky rock layers.

During an exploration deep inland, she discovered another fossil in the rock face of a limestone cliff. The texture of this fossil was exactly the same as the one she had found before, but its size was astonishingly large. It was ten meters long, like a prehistoric whale.

Mira couldn't help but wonder, could this be the only type of fossil found on Mars? Was this the only life form that existed on this planet? Or was it that only this specific type of organism could form fossils?

After sunset, she returned to her living quarters on time.

The world inside the inflatable dome was like paradise, filled with abundant and warm liquid, luxurious enough to heat a whole liter of pure water at once for her to wash. When the warm water droplets slid over her skin like silk, the experience was simply the ultimate pleasure.

Her throat was no longer so sore, and she could even speak at a normal volume louder than a whisper.

She washed away the dust, carefully braided her blonde hair, and deliberately dressed very lightly inside the cabin. She knew very well that it was Song Xingye's turn to make the decision. 140 kilograms—out of the three of them, he could only take one home.

However, Song Xingye seemed to ignore her completely. Despite her racking her brains and using more than a dozen subtle and indirect methods to flaunt herself in front of him, displaying herself almost from all angles in the cramped living quarters, he should have been able to notice. But he remained unmoved and made no response.

……

The Butterfly was originally designed for short-distance jumps and aerial reconnaissance, and was never intended to be manned, let alone to undertake long voyages of up to two thousand kilometers.

Song Xingye removed all unnecessary flight components, redundant control systems, and scientific instruments. He even sawed off the landing gear. When the "Butterfly" landed, it could only make a forced landing on the snow using its belly. In any case, this plane would never be able to fly again.

It was a gamble with no chance of winning, but at least now he has a plane that can barely reach the poles.

To complete the launch, Song Xingye first laid two ultra-fiber cables with a total length of three kilometers on the sand. He fixed the far end of the cables to the anchor bolts drilled into the rock strata, and then returned to the launch area to begin stretching them with an electric winch.

These microfiber cables accumulate terrifying elastic energy. If they suddenly break, the cables will rebound instantly with a terrifying impact force close to the speed of sound, releasing enough energy to instantly vaporize the cables themselves and the people around them.

He secured the fully stretched cable with a second anchor bolt, making it resemble a giant rubber band several kilometers long. Next, Song Xingye would use this, the world's largest "slingshot," to launch the aircraft into the sky.

The plane only had two seats, so Mira and Han Jing had to squeeze into the co-pilot's seat, with Mira even having to sit on Han Jing's lap. The two of them were wearing bulky Mars suits and could barely move in the cramped cabin.

Song Xingye quickly closed the hatch and sealed it shut, then sat down in the driver's seat.

"Are you ready?" Song Xingye asked.

"That's the only way," Han Jing replied in a low voice.

"Come on!" Mira said.

"System ready," Song Xingye said, pulling the safety pin from the remote control and shouting, "Launch!"

A sudden explosion rang out, and Song Xingye felt a flash of light tear through the night sky behind him. The straps securing the microfiber cable were instantly snapped, and the "microfiber slingshot" hanging on the engine mount suddenly contracted and exerted force, pressing everyone firmly into their seats with terrifying thrust.

Han Jing cried out in alarm from behind, "Good heavens!" Mira also let out a painful groan due to the sudden overload.

The ground rushed past the window at an alarming speed. Song Xingye was completely focused on keeping the wings level. Even if the wingtip just lightly grazed a bit of the sand, the fragile plane would instantly disintegrate around them.

He had no time to pay attention to the speedometer; he could only rely on his intuition to feel the resistance of the airflow pulling the wings. He pushed the control stick forward and pressed down hard on the nose of the plane so that it could reach the critical speed for takeoff as soon as possible. He glanced at the instrument panel quickly; it wasn't enough, it was still a little short.

Right now.

He slowly pulled the control stick back, making sure the movement wasn't too big, otherwise the wings would break off and the ground would gradually recede from beneath their feet.

At this moment, the "Butterfly" rose into the air like a kite being pulled up by a child running wildly. The tension of the cable began to weaken, and the kinetic energy of the catapult was about to be exhausted.

It only took a few seconds. He held his breath and maintained his flight posture, trying to squeeze out the last bit of lift from the rapidly loosening slingshot.

The tension of the cable dropped sharply and then broke off. The "Butterfly" was completely freed from its restraints. Song Xingye quickly opened the liquid oxygen tank valve, turned off the ignition switch, and stared intently at the indicator light. After a terrifying pause of one second, the green light finally came on.

Everything is ready.

Song Xingye pressed the main ignition button, and with a violent tremor, the ramjet rocket roared and spewed out a blazing tail flame.

For the first time in weeks, hope ignited in Song Xingye's heart. Perhaps they really could succeed. They were taking flight!

……

From the air, Mars presents a completely different appearance.

Song Xingye flew the plane at low altitude. Due to the severe overload of the "Butterfly" spacecraft, he had to stay close to the densest part of the Martian surface in the thin atmosphere in order to barely maintain lift.

Even so, the magnificent sight before them was breathtaking; from a bird's-eye view, they were sailing along the coastline of an ancient ocean.

To the east are scattered mountains and chaotic landforms, with ancient riverbeds crisscrossing the surface, as if you can still see the traces of rivers flowing into the ocean millions of years ago. To the west is a vast and flat basin with a few meteorite craters scattered around.

Han Jing was pressed against the porthole, completely absorbed in the view. He turned around, intending to point out the majestic mountains on the horizon to Mira, but was surprised to find that she had her eyes closed and was asleep.

She actually fell asleep during the most awe-inspiring flight in human history!

As the liquid oxygen was gradually consumed, the aircraft's weight decreased, and Song Xingye gradually stabilized his flight attitude.

"There is no such thing as a plane that can fly on its own," his flight instructor warned him years ago on another planet. "You must always be vigilant. When you think the computer can take over everything, when you relax your vigilance and become careless, accidents will happen. Pilots often die in these moments."

At this moment, the aerodynamic performance of the "Butterfly" is perfect. After completing the takeoff phase, Song Xingye could actually release the control stick and hand over the autopilot system. Currently, they are flying straight north.

The landscape below had been repeatedly sculpted by massive impact craters and vast lava flows. As they traveled north, Song Xingye discovered some peculiar meteorite craters with eerie molten edges, as if the meteorites had not struck hard rock but splashed into a large bowl of thick ice cream.

Of the three liquid oxygen tanks, the first one was almost empty. Song Xingye opened the valve and switched to the second tank for oxygen supply. The engine made a violent jolt due to the instantaneous change in fuel flow. He then returned the evaporated gas to the first tank, completely emptying the remaining oxygen inside.

After confirming that the inside of the tank was completely dry, he pressed the jettison button, freeing the empty tank from its dead weight and wind resistance, and the "Butterfly" lightly rose a short distance upwards.

There are two liquid oxygen tanks remaining.

As the line of sight extends northward, large patches of white begin to come into view. At first, it was just a thin wisp of frost-white dotting the edge of the northern slope of the ring mountain. Gradually, the white frost and snow began to spread and spread in layers, like a spider web weaving between the hills, outlining the subtle undulations of the terrain with exceptional clarity.

He is approaching the Arctic Circle.

Song Xingye looked up and saw that the sky in front of him had lost its pale yellow ochre color and was replaced by an ominous deep brick red, with dark red patches and violent air currents intertwined and interwoven within it.

He cursed under his breath, glanced at the altimeter, and saw that they were only 1,100 meters above the ground. He pulled up the nose slightly, trying to gain more altitude, but this meager height was clearly not enough for them to fly over the storm.

He noticed something moving below.

It's a snake.

He looked closely and saw that on the ground beneath his feet, white ribbons formed by accumulated snow were winding and meandering like living snakes. He suddenly realized that they were snow rivers whipped up by the wind and flowing rapidly down the lowest pass in the valley.

The wind speed on the surface must be extremely high. In the thin atmosphere of Mars, it would require winds of at least fifty meters per second to forcefully lift and blow away the snow on the surface.

Spring is arriving at the Martian poles. As sunlight returns, the winter snow cover, formed from carbon dioxide and water ice, begins to sublimate dramatically. Large amounts of vaporized gas throw the remaining water ice particles into the high atmosphere and blow them southward, creating small-scale localized storms at the edge of the polar caps.

Head-on collisions would be tantamount to suicide. Fortunately, these storms were only localized weather events and did not cover the entire globe. He decisively turned westward, keeping parallel to the approaching cumulonimbus clouds, attempting to bypass the storm's core and find gaps between the individual storm cells.

At this moment, the land below had completely turned into a polar tundra. He had officially entered the Arctic Circle, with snowflakes whipped up by the gale at his feet and huge, abrupt ice blocks scattered across the ground.

Even more bizarrely, the ground is covered with strange landforms composed of polygons, with huge hexagons, triangles and squares interspersed, like a grand jigsaw puzzle pieced together by nature, almost like the astonishing work of a mad geometer.