There was a dead silence in the hall.

This time, Tang Yue heard clearly, there was indeed something knocking on the door outside, and it was knocking on the inner hatch of the airlock room...... He had thought that it would be the sound of sand and gravel blown up by the strong wind hitting the Kunlun station, and it is said that this kind of thing is common in the plateau radar station on the earth, and the sudden strong wind flying sand and rocks, and the stones smashing on the walls and gates with a thud.

But Tang Yue quickly ruled out this reason, there is not such a large air density on Mars, and no matter how fast the wind speed is, it can't blow the stones up.

He was stunned for a few seconds, his brain racing but he couldn't find the instructions to give to his limbs, Tang Yue had been trained so much, and there had never been a single training that told him what to do when someone knocked on the door outside Kunlun Station.

There is certainly no entry in the mission manual for Neil Armstrong's moon landing that year, "What to do when you open the door of the lunar module and see not a barren lunar surface, but a ceremonial welcome party".

The old cat reacted faster than him.

It picked up a steel pipe in its hand, clenched it tightly in its claws, and then yelled at Tang Yue: "Mingguang Armor! Tang Yue! Put on the Bright Light Armor! ”

Tang Yue jumped up, rushed out and put on the Mingguang armor, the old cat pounced on Tang Yue to protect him, holding the steel pipe with one paw and carrying the can with the other, as if facing a great enemy, look at its posture, if the next moment the hatch is pushed open, it will smash the can out.

It's a pity that it's not a combat type, otherwise it should pull out an AKM automatic rifle.

Tang Yue hurriedly put on the Mingguang armor, buckled the life support system, turned on the oxygen supply, and protecting himself in an emergency situation is always the top priority, even if the Kunlun station breaks the pressure in the next moment, Tang Yue will not be suffocated immediately, and the protection of the Mingguang armor will leave enough buffer time.

"Old cat?"

"Back off." The old cat pointed behind Tang Yue and whispered.

There was no sound outside the door, and the old cat stared at the airlock hatch, not knowing what the knock was or whether it was still outside.

"Back off." The old cat motioned for Tang Yue to retreat again.

Tang Yue retreated all the way to the wall.

The old cat lightly took off the cabin suit hanging on the wall, buckled the mask with four legs, and turned his head to look at Tang Yue, "I'll take a look, you stay there and don't move." ”

Tang Yue nodded.

The old cat gently put the can in his hand on the table, the steel pipe changed to a paw to take it, and then approached the airlock hatch step by step, the barometer next to the door showed that the air pressure in the airlock was much lower than the standard atmospheric pressure, less than one percent of the standard pressure, which is the data of the surface atmospheric pressure of Mars, which indicates that the airlock has just passed through the outside world, and at the same time means that something has indeed opened the outer hatch - that thing is from the outside world.

The circulatory system began to pour air into the airlock, and the air pressure gradually increased, which was on par with the air pressure in the hall, while the old cat clung to the turntable in the center of the hatch and turned it slowly and calmly.

It does not use electronic unlocking, and the advantage of opening the door purely manually is that the operation can be stopped at any time in the event of an accident.

With a "click", the heavy cylinder slowly retreated.

The old cat's face sank like water.

It pushed the hatch with a steel pipe, slowly pushing it open.

Tang Yue curiously tried to look around.

For humanity, this is likely to be a historic moment – no less significant than Gagarin's flight into space, Armstrong's landing on the moon, Kunlun's inauguration on Mars, and Tang Yue's possibility, and perhaps the first human in Earth's history to come into contact with an extraterrestrial civilization, and certainly the last.

The old cat frowned.

It thought more than Tang Yue, and of course it was more flustered than Tang Yue, and its composure was forced.

The moment there was a knock on the inner hatch of the airlock, the worldview inherent in the old cat's mind had collapsed - this was the idea instilled in it by the engineers who made it, and behind it was the result of all mankind's observation and cognition of this universe, which was rigorous, reliable, indestructible, and built on unshakable physical and mathematical logic.

But in the past second, the narrow perception centered on the earth and humanity itself, which has taken thousands of years to build up by human civilization, has been completely destroyed. Although human beings have looked up at the starry sky for thousands of years and thought about extraterrestrial civilizations for hundreds of years, this kind of thinking is not fundamentally different from the pantheism of primitive man who worships heaven and earth and nature - they are all derivative products that take themselves as a template and are centered on themselves.

It's an innate centralization.

But at this moment, the human mind is inevitably decentralized.

The world is bigger than ever.

The old cat thought that his existing cognition was unbreakable, because it was essentially mathematics, reasoning, logic, one plus one equals two, as long as one plus one equals two and there is no error, then it is impossible to make mistakes. You have to let it prove why it can't observe extraterrestrial civilizations, the old cat can give you hundreds of evidence from all sides, each of which is blameless, but you have to prove that extraterrestrial civilizations are around, don't say anything, just let it knock on the door outside Kunlun Station.

In the words of the old cat, this soft "thump" was as terrifying to it as the Big Bang.

This universe is far more complex than anyone thinks.

The hatch is open.

Tang Yue took a deep breath and widened his eyes, ready to welcome this historic moment.

He had prepared his lines, still quite formal diplomatic rhetoric.

"We strongly condemn your false ...... to us"

I got the wrong draft.

“That’s one small step for a man，one giant leap for mankind.”

The first thing that catches your eye is the white bulkhead, there is a ring of stiffeners on the inner wall of the cylindrical airlock cabin, the top of the airlock chamber is lit with LED lights, and there are fine sand particles on the floor, and the old cat and Tang Yue are directly opposite the round outer hatch, and there is also a manual unlocking turntable in the center of the hatch, just like the cabinet door of the safe, the outer hatch is closed, and the indicator light is red, indicating that the hatch has been locked.

The old cat and Tang Yue's eyes walked over and over, swept every corner of the airlock room, and then were stunned.

The airlock chamber was empty.

Nothing.

Tang Yue stepped forward and stood side by side with the old cat at the door, frowning.

"Empty?"

The old cat put down the steel pipe and nodded, "Empty." ”

It secretly breathed a sigh of relief, the airlock chamber was empty, there was nothing, then the sound just now could be directly eliminated with Occam's razor, maybe it was not a knock at all, but the sound of the structure of Kunlun Station trembling or something else, it was a normal natural phenomenon, not an alien creature knocking on the door.

The old cat's worldview doesn't have to collapse.

"What was that sound just now?" Tang Yue raised his head and looked around.

"It may be that the hinges of the hatch are unstable and there was a collision." The old cat replied, "It could also be the sound of parts falling off." ”

Tang Yue was not satisfied with this explanation, he still remembered the sound just now, Tang Yue could be sure that it was definitely not a part falling off, but the sound of someone bending his knuckles and tapping on the cabin door.

But the old cat's explanation is the most realistic.

In real life, how can there be so many strange things that cannot be explained?

There was a false alarm, the old cat turned around and wanted to put the steel pipe back, at this time Tang Yue suddenly grabbed its arm, "Old cat ......"

"What's wrong?" The old cat turned his head.

"Old cat...... You...... You...... You, you, you, you look at ......" Tang Yue pointed to the floor under his feet, "Look at the floor!" ”