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

He had flown far enough to see the entire hatch ahead.

It was a bright fluorescent object embedded in the hull of the Challenger.

Inside the hatch, Sheng Tianhong was crouching down, looking at him through his helmet and nodding occasionally.

He continued to move backward, still using his right leg for support as he crawled and groped his way forward on the porch, until finally his toes touched the top rung of the ladder.

He gripped the handrail tightly and straightened his body.

He was gradually disappearing into the shadow of the Challenger. The ship's massive hull blocked the rising sun, and the sky above remained pitch black, with only the stars gradually fading into darkness.

He slowly turned around, and on both sides were flat horizons, marking a plain of dust and rocks.

Everything here seemed to be stained with a rusty brown color, like a pool of dried blood, which made people feel a little scared.

The MEM Mars lander has been docked on the Martian surface for three days.

The crew had to spend this precious time adapting to the new low-gravity environment.

As expected, Song Xingye found that he was a few centimeters taller than when he left Earth, and he also felt that he was about fifteen grams lighter.

At first, in the cramped compartment of the landing module, he could barely walk, either bumping into the bulkhead or not being able to tell which way was down.

His legs also became exceptionally thin due to muscle atrophy.

Although the three were trapped on the surface of the red planet, Mars' gravity was only one-third that of Earth, so his thin legs were enough to support his body.

However, after three days on the surface of Mars, he still felt dizzy and disoriented, as if the sunlit scene outside the window was just another cheap imitation made of plaster.

But as he was about to step out of the cabin, all of this finally became a tangible reality.

Sheng Tianhong met him at the airlock hatch.

Both of them were wearing thermal underwear, with liquid-cooled ventilation suits covered with corrugated water-cooling pipes on the outside.

Song Xingye had already inserted a catheter, while Sheng Tianhong was wearing his urine collection device, which looked like a strangely shaped giant suit.

Their attire was both ridiculous and utterly unappealing.

"The scenery is beautiful, isn't it?" Sheng Tianhong murmured. "You know, Mira said she can see Mars' moons with the naked eye."

"Perhaps, that's certainly possible."

The satellite should now appear as a faint, silvery-gray glow, slowly orbiting the red host star.

Sheng Tianhong brought over Song Xingye's lower body assembly, which was the lower half of the EVA spacesuit, along with his pants and boots.

"Come on, Lao Song, stop looking at the scenery."

Song Xingye stared at the spacesuit, feeling as if he were in a dream.

"We've waited too long for this moment, haven't we?"

"The long wait is over."

Song Xingye put the finger ring on the cuff of the liquid cooling suit on his thumb to prevent the sleeve from slipping up during subsequent activities.

He examined his hands, his familiar skin revealing plastic tape wrapped around the base of his thumbs to prevent friction.

This was the first step in putting on this complicated set of equipment, and even this simple action made his heart race.

He lifted his leg and stepped into the lower torso assembly.

This thing is so bulky it's uncomfortable; the layers of fabric are incredibly stiff.

When Sheng Tianhong tried to help him pull up his trouser leg, it twisted and resisted between his legs as if it were alive.

Song Xingye found himself panting heavily, his physical strength severely depleted.

He then connected the catheter to a urine storage bag, which was large enough to hold a few pints of liquid.

As for the issue of excretion, there is no need for additional collection; he wears a highly absorbent undergarment, which is essentially a diaper.

According to the euphemistic wording in the training manual, it can absorb "any uncontrollable bowel movements during EVA activities outside the cabin".

However, Song Xingye was determined to hold back no matter what.

Next comes wearing the rigid upper torso component HUT.

This part resembles a half-body suit of armor, currently suspended on the wall of the airlock, with a life support backpack attached to its back.

He crouched below HUT, raised his arms, and twisted his body to crawl upwards into the hard shell.

The inside of the casing is dark and filled with a mixed smell of plastic, metal and fabric, giving it a fresh, recently manufactured feel.

He slowly tucked his arms into the sleeves, and finally his hands emerged from the cuffs. The rings on the cuffs of the liquid-cooled suit tightly constricted the soft skin around his thumbs.

In order to get it on, his shoulders were forced to bend backward painfully.

The entire process of putting it on is anything but easy.

However, compared to the earlier Apollo lunar suits, this spacesuit is relatively simple. Back then, the command module astronauts had to manually assemble the spacesuits on the lunar surface and personally connect the water and oxygen supply lines in their backpacks.

His head finally popped out of the collar.

Sheng Tianhong grinned and teased him, "Welcome back to the human world."

Sheng Tianhong forcefully pulled the upper torso component down to fit Song Xingye's shoulders, and then aligned the two halves of the metal waist ring.

Sheng Tianhong forcefully pulled the upper torso component down to fit Song Xingye's shoulders, and then aligned the two halves of the metal waist ring.

With a "click," the equipment was locked shut perfectly.

Then, Song Xingye helped Sheng Tianhong get dressed.

The two had been in the cramped airlock for two hours.

The Challenger spacecraft maintained an environmental pressure of 70% of that at sea level, with the air consisting of a mixture of nitrogen and oxygen. However, to ensure that the spacesuit retained some flexibility after inflation, it was filled with pure oxygen at a pressure only one-quarter that at sea level.

To prevent decompression sickness, they must inhale pure oxygen beforehand to expel dissolved nitrogen from their blood.

This is simply a headache-inducing and physically exhausting ordeal.

On Mars, each extravehicular activity can only last for a maximum of three or four hours.

Back in the Apollo era, backpack-style spacesuits could support seven hours of work on the lunar surface. However, the gravity on Mars is more than twice that of the moon, so the spacesuits had to be lighter, which greatly shortened the effective time for extravehicular activities.

Even worse, after each activity, a lengthy cleaning process is required, where Martian dust on the spacesuit must be carefully removed with a vacuum cleaner.

If these fine powders containing strong oxidants were to get into the spacecraft, they would definitely cause severe burns to the astronauts' respiratory tracts.

Every day on Mars was long and tedious.

For that brief spacewalk, they had to spend most of the day on tedious preparations, cleaning, and repeated wiping with anti-contamination swabs.

Song Xingye put on the communication soft helmet, commonly known as the "Snoopy hat," and then picked up the hard helmet with the gold-plated face mask from the helmet frame, clipped it into the sealing ring around his neck, and rotated it to lock it in place.

Finally, gloves were put on, which tightly wrapped around the wrists and were locked in place by metal clasps at the wrists.

Sheng Tianhong lightly flicked the switch on the control panel on his chest, and Song Xingye immediately heard the familiar hum of the water pump and fan running in his backpack, as cool oxygen whistled through the inside of his mask.

Sheng Tianhong gently tapped the top of Song Xingye's helmet and raised his thumb, which was covered in a heavy glove, in front of the transparent visor.

He nodded to Song Xingye, a smile playing on his lips.

Song Xingye raised his arm and, using the small reflective mirror sewn onto his cuff, clearly read the real-time data on the front panel of his chest: blood oxygen saturation, carbon dioxide partial pressure, airway pressure, and various fault alarm indicator lights.

At this point, the pressure inside his spacesuit had stabilized.

Sheng Tianhong tested the radio communication: "Can you hear me, Lao Song...?"

Due to the extremely low air pressure, his voice sounded both soft and shrill, accompanied by a muffled echo coming through the thick glass mask.

Song Xingye looked down to check the water tube protruding from the inside of his helmet, took a few sips of water, and then drank some orange juice.

The orange juice tasted alright, but the water was too hot from my body heat.

But none of that mattered. He briefly pushed the pressure inside the spacesuit to its peak to conduct a final leak test.

He then attached the spiral-bound checklist for extravehicular activities to his sleeve.

After they finished dressing, the two looked each other up and down.

Sheng Tianhong's spacesuit was snow-white and brand new, paired with bright blue Mars mission-made over-the-knee boots, and the bright flag red on the shoulders and sleeves was particularly eye-catching.

"Is everything settled?" Sheng Tianhong asked.

After the life support umbilical cord connecting him to the Challenger was disconnected, Song Xingye was completely sealed inside the miniature single-person spacesuit.

He took a deep breath of the cool, pure oxygen and replied, "Okay, let's begin."

"Received." Sheng Tianhong turned to Mira, who was in the upgrade pod, and reported, "Mira, we are in position and awaiting the 'decompression' command."

"Received, Tianhong. You can begin decompression." Mira will monitor this first-ever extravehicular activity on Mars from inside the ascent module.

Sheng Tianhong pressed the pressure relief switch on the bulkhead, and Song Xingye could hear the hissing sound of air flowing out.

As the outside air pressure decreased, the noise of his own breathing became louder and heavier inside the helmet, completely drowning out the already faint sounds from the outside.

"Understood," Sheng Tianhong said. "Everything is ready now. We just need to wait for the pressure inside the airlock to drop enough to open the hatch."

Song Xingye glanced at the pressure gauge, and the reading had dropped to 0.2 grams per square centimeter.

Mira's voice came through: "My telemetry data shows that the static pressure in the airlock is extremely low. Do you think we can open the door now?"

"I'll give it a try," Sheng Tianhong replied.

The hatch is located near the bottom of the hold and is very small. The handle is a simple mechanical lever.

Sheng Tianhong bent his heavy back, twisted the handle, and pulled backward with all his might.

Song Xingye saw that the thin metal plate of the hatch was even slightly dented inward under the force, but the hatch was still firmly stuck.

The gloves, covered in metal mesh and rubber, were maddeningly clumsy, and his hands appeared unusually large and sluggish at that moment.

But he managed to pry open a small crack in the hatch with all his might.

A ray of ochre-colored Martian light poured in through the gap between the hatch and the frame.

"I think I've opened the seal."

Sheng Tianhong pulled the handle again, and this time the hatch opened easily inward.

As the last wisp of air in the airlock suddenly escaped and dissipated into the extremely thin Martian atmosphere, Song Xingye witnessed a brief and strange snowfall due to the rapid expansion and cooling.

The two had to step back to make room for the inward-opening hatch.

Immediately afterwards, Song Xingye saw the extravehicular activity platform suspended above the Challenger's sturdy landing legs, and they were about to back up onto it.

The metal mesh on the platform surface was covered with brown gravel kicked up during landing.

Beyond the edge of the platform, the Martian surface came into view, with stripes radiating outwards from the Challenger on the flat sand. These were the spectacular works left by the landing engines during their final deceleration thrust.

It was a desolate and lifeless landscape, but if he saw a similar desert on Earth, he wouldn't even give it a second glance.

But at this moment, he was truly in the Mangala Valley on Mars, separated from this red land he had devoted his life to studying by only a few meters away by an extremely thin layer of alien atmosphere.

"Old Song," Sheng Tianhong suddenly spoke.

Song Xingye turned his head.

In stark contrast to the boundless ochre-brown of Mars outside the door, Sheng Tianhong's pristine white spacesuit gleamed faintly under the dim lights inside the airlock.

"We missed a checklist step," Sheng Tianhong said calmly. "It's on the checklist. We haven't finished it yet."

Sheng Tianhong took out the red EV1 Extravehicular Astronaut Identification Straps from the outer thigh pocket of his spacesuit.

As the commander of the first Mars landing mission, Sheng Tianhong was supposed to lead the entire operation, and Song Xingye was just his official substitute.

According to regulations, Sheng Tianhong had to have these striking red stripes tied to his spacesuit on his limbs so that television cameras broadcasting live worldwide could distinguish him from his substitutes.

But he kept these straps on his person without permission.

"I don't understand you."

Sheng Tianhong laughed again: "I think you understand, Lao Song, tie these straps on."

Song Xingye subconsciously reached out his hand, and Sheng Tianhong stuffed the red bandages into his palm.

Through the thick spacesuit gloves, he couldn't feel their weight at all.

"You must be joking." Song Xingye said incredulously.

Sheng Tianhong seemed a little impatient: "Listen, I'm not asking you to pilot this damn landing capsule alone. You can do this kind of extravehicular activity procedure with your eyes closed in emergency simulation training. For this first extravehicular activity, you just need to walk out of the hatch, wander around, pick up a few stones, and then say something casually to your family and audience on Earth."

Sheng Tianhong's shocking suggestion did not bring Song Xingye any joy or pride; instead, it only filled him with irritation.

My emotions were tossed around like a rollercoaster.

"This is absolutely absurd, Tianhong! You're actually giving up the chance to become the first human to set foot on Mars? Good heavens, what the hell are you doing?"

"This is humanity's first ever extravehicular activity!" Sheng Tianhong was also somewhat annoyed. "This is the most important thing, Lao Song. We've discussed this countless times before launch. We must ensure that this extravehicular activity goes perfectly, especially this first step, for the future of all humanity. The next few minutes may be the core of the entire Mars mission."

It's even more important than its scientific value, though I don't expect you'll agree.