The next day.
The twentieth simulation test.
"Mr. Cat, Tang Yue, I'm in position."
Mai Dong put on an extravehicular spacesuit and sat back in the commander's seat of the Eagle lander. She fastened her seatbelt, and the protective cover of the lander's porthole was all closed.
"This is Kunlun Station. Roger that," Tang Yue replied. "Make sure to maintain communication."
"Orion II system computer offline."
"Atmospheric model modeling complete. Lander aerodynamic parameters modeling complete. Navigation error correction."
"The computer has entered EDL mode. The GNC system is normal. The guidance control program is fixed. The GNC data will be updated three minutes before entering the atmosphere. The radial altitude is 125 kilometers, and the distance between the core of the fire is set as the GNC time sequence command EDL zero."
"Communication frequency band switching for atmospheric entry is normal. UHF band signal is good. X band signal is good."
Old Cat sat across the table, surrounded by monitors and keyboards. It was using all four limbs — indeed, it was using all four limbs. Old Cat sat with its butt tilted, and placed a keyboard on the chair in front of it for its toes to use.
Old Cat was using a set of Two Toes Zen Technique as it danced on the keys smoothly.
"IMU normal. Decoupling command triggered five minutes before entry."
"Mass trim, flight path angle adjustment, minus 11 degrees. Angle of attack adjustment, minus 5 degrees."
Old Cat and Tang Yue's voices rose and fell in Kunlun Station.
In Old Cat's words, this test was in the bag. It had spent a long time correcting Orion II's control program. It did not sleep or rest at all, striving to ensure that every detail was foolproof.
They lacked the conditions to conduct a physical test, so they could only simulate it in virtual software. Old Cat had set up the harshest test environment, just to leave as much room for maneuvering as possible for the real Orion.
The Old Cat was doing its best. If it failed again, it did not know how to solve the problem.
Both man and cat firmly believed that since it was theoretically feasible, then there must be a possibility of success. No matter how low the probability was, whether it was one in ten thousand or one in a hundred thousand, as long as it existed, then no one could stop them from approaching the limit through repeated trial and error.
No matter how low the probability was, it was still limited.
But there is no end to human subjective initiative.
This is what Marx said.
Old Cat commented that the old man was only half right.
This was because the subjective initiative of a cat was endless.
"The inertial coordinate system has been established. Kunlun Station is normal. All departments of Orion are normal. Raptor-01, 03, 05, 07, and 09 are normal. Prepare for countdown. All departments, attention —"
Tang Yue raised his head and looked past the monitor at Old Cat.
Old Cat was burying its head in between the computer monitors. It noticed Tang Yue's gaze and nodded slowly.
"Miss Mai Dong."
"Yes." The girl nodded.
Old Cat and Tang Yue stood on both sides of the table and stared at the monitor screen. Tang Yue raised four fingers and began a silent countdown. Four!
Old Cat raised three toes.
Three!
Tang Yue raised his index and middle fingers high above his head and roared in his heart.
Two!
Old Cat gave a thumbs up. One!
The engine ignited!
The 745 second countdown began!
Orion II's Earth Fire Transfer Spacecraft entered the atmosphere for the twentieth time!
The five Raptor engines ignited at the same time. The scorching hot jets drew a sword-like trace in the dark sky. The violent vibrations were transmitted along the fuel tank and the metal truss. Orion II's huge body began to decelerate and fell along the predetermined flight path. The huge overload pressed on the main structure of the spacecraft layer by layer. Fortunately, the computer's control was accurate enough that the central axis of the spacecraft did not deviate from the predetermined angle.
Gravity and the engine's thrust compressed the spacecraft longitudinally. This was a challenge for Orion's structural strength. The slender structure of the spacecraft was very fragile in the gravitational field. It would break if it was bent. Therefore, Old Cat had to make all the forces act along the longitudinal axis. It could only be subjected to pressure and not shear.
Orion II's computer began to rapidly alarm.
The sensors all over the spacecraft were reporting the force applied. In the simulation test, these data were given by the Kunlun Station's workstation. Old Cat was doing his best to simulate the situation. When the spacecraft actually landed, the situation would be the same.
In Tang Yue's words, Orion II was hanging by a thread. It could not be disturbed in any way, and no one could touch it. Otherwise, the strand of hair that hung the heavy object would break.
"118774.6 meters above sea level, 4,727 meters per second!"
"115054.9 meters above sea level, 4,591 meters per second!"
"106932.2 meters above sea level, 4,378 meters per second!"
Tang Yue propped his hands on the table. He could no longer sit still, but there was nothing he could do. All he could do was stare intently at the spacecraft. Tomcat had told him that this was the simulation with the highest chance of success. This was because it had designed the program to be foolproof. It couldn't find any problems. If the test failed again, even Tomcat wouldn't be able to do anything.
Orion II's altitude was rapidly decreasing. Almost all the sensors were alarms. The force applied to the spacecraft's structure had completely exceeded the design limit.
"The atmospheric density is increasing. Pay attention to turbulence. Pay attention to turbulence. Very good!
The RCS is stabilizing. The deceleration is in line with expectations! "Old Cat excitedly clenched his fist." Steady … Steady, bastard … "
Orion II had to slow down before the atmospheric density increased dramatically. Otherwise, the intense friction with the atmosphere would burn the spacecraft.
"97335.4 meters above sea level, 3,945 meters per second."
Old Cat stared at the temperature and pressure sensors. The temperature of the temperature concentration area had risen to 300 degrees Celsius. Some parts and coatings that could not withstand the high temperature had begun to melt. However, this was within the tolerance range of the spacecraft. In the world of numbers and codes formed by the workstation, Orion II was steadily descending.
"GNC system data updated again. Mass balance, trajectory angle adjustment!"
"Code 1027 alert!"
"Code 1160 alert!"
Tang Yue's forehead was full of cold sweat. He and Old Cat were powerless to change the fate of Orion II. The only one who could save it was itself.
He and Old Cat watched the spacecraft descend ten thousand meters, ten thousand meters. Although the total time from re-entry to landing was only twelve minutes, every second was extremely difficult for Tang Yue. He was afraid that the next second, the computer would pop up a problem and tell him that the spacecraft had lost control and crashed.
Orion II was descending with scorching flames. There was almost no oxygen in the Martian atmosphere. The light was actually the volatilized and melted material on the surface of the spacecraft. The outer coatings and parts were constantly peeling off in the violent tremors. Fortunately, they did not affect the stability of the spacecraft.
The air was compressed into shock waves at high speed. During the landing process, this layer of plasma would isolate electromagnetic waves and obstruct communication. It was called the "black barrier." However, Orion II's speed was strictly controlled, so the black barrier was not serious.
"35783 meters above sea level. All departments, attention. We are entering the high heat zone."
At an altitude of around thirty thousand meters, Orion II would experience its first life and death situation. At this altitude, the exterior temperature of the spacecraft would rise to the highest. In the past ten simulations, half of them had failed at this altitude.
The structure and materials of each part of Orion II were different. Some parts of the power module could withstand temperatures of more than two thousand degrees, but the command module could only withstand up to four hundred degrees. In this case, the difference between life and death was the short part. Once the command module's temperature exceeded four hundred degrees, it would immediately burn down.
"32580 meters above sea level," Old Cat reported.
"Temperature sensor warning. The cooling of the system computer is not normal." Tang Yue immediately said, "External temperature is 332 degrees."
"31932 meters above sea level."
"355 degrees."
"31541 meters above sea level."
"362 degrees."
"30274 meters above sea level."
"375 degrees!"
Orion II passed through the atmosphere against the scorching airflow. The engine roared as it tried its best to slow down.
"29289 meters above sea level."
"388 degrees!"
"393 degrees!"
"395 degrees!"
The temperature sensor's data continued to climb.
"398 degrees!"
"400 degrees!" The thermometer reached its peak and touched the red line. Tang Yue's heart suddenly shrank.
"Orion II has successfully decelerated. It has broken through the high heat zone!"
Old Cat's words were late by a second. Both man and cat held their breaths. Kunlun Station fell into silence. The icons on the monitor flashed rhythmically.
Although the spaceship had already broken through the high heat zone, the temperature just now had already reached its resistance limit. Disaster could be brewing in the silence. No one knew if the high temperature would cause the structure to melt and become brittle, eventually causing it to fall apart. No one knew if Orion II would have a problem, or if a window would pop up in the next second to report that it had crashed.
Tang Yue clenched his fists.
Old Cat pressed on the earpiece.
Half a minute later.
There was no alarm, no crash. Tang Yue and Old Cat both saw the temperature data begin to drop. Orion II's system computer's self-check was normal, and the spaceship landed steadily.
"Orion II is descending normally … Descending normally!
It survived!
It survived! "
Tang Yue climbed up and excitedly held onto Old Cat's shoulder. He looked into the cat's eyes and laughed. "Hahahaha!
That child survived! "
Three hundred seconds after entering the atmosphere.
Orion II successfully broke through an altitude of 10,000 meters.