"The first step is to unload the damaged Dawn module."

The old cat circled the module at the end of the United Space Station with the mouse, and the Dawn module was still docked on the crystal module, but it had long been abandoned, and all power and control were cut off.

Mai Dong held her laptop in her arms, with a mess of data cables floating around her, huddled between the layers of control panels, her face illuminated by the white backlight of the computer monitor.

"Mr. Cat, the hatch is locked, the system self-test is complete, the space station is in normal condition, and Orion II is in normal condition."

"Kunlun Station received."

"The generator is ready to ignite." Mai Dong reports, "Raptor-02 Preparation, III, II, I...... Ignition. ”

The space station trembled slightly, Mai Dong raised his head, the vibration was transmitted from the bulkhead to the data line, the energy progressed along the slender black wire, and the floating pen and paper reacted much more slowly, they still floated leisurely in the air, there was almost no interaction between these suspended objects and the space station in the weightless environment, they were independent individuals from a certain angle, just flying at the same average speed of three kilometers per second.

Orion II's rocket engine starts again, propelling the station to rotate with very small thrust, an attitude adjustment to unload the Dawn module.

"The roll of the Joint Space Station is complete, the attitude is stable, and Raptor-02 is shut down." Mai Dong turned off the engine, "Mr. Cat." ”

"Okay, well done, you're a very skilled spaceship pilot now, Miss Maidon." The old cat nodded, "The super big arm is locked, all pay attention...... Disconnect the mechanical connection. ”

As soon as the old cat's voice fell, Mai Dong felt that the core module shook slightly, which means that the Dawn module was officially separated from the core module, since the old cat cut off the power and control connection nine months ago, the last mechanical docking was also disconnected, and the veteran module that existed at the beginning of the establishment of the joint space station has finally completed its historical mission today, and it can be retired with peace of mind.

The Super Boom swept through the porthole with the Dawn module, and Mai Dong watched it disappear behind the solar panels.

"Mr. Cat, did you release it?"

"It's released, and it will be in orbit around Mars for about three months." The old cat said, "And crashed inside the atmosphere." ”

The girl closed the laptop in her hand, and her super arms folded not far away.

"In the second step, we are going to modify the Orion and the United Space Station! After the Dawn module is removed, the space left will be used to dock to the compartment on the Orion spacecraft, which sounds simple, but the same work will take at least half a month in Earth orbit. The old cat paced in Kunlun Station, highly concentrated, and while sorting out its own logic, it described the work steps in a loud voice.

"The module on the central module of Orion II, except for the command module, the other seven modules will eventually be dismantled." The old cat sat on the table, holding the monitor in his arms, and pointed out the schematic diagram to Tang Yue and Mai Dong, "The optimal plan is as follows: first remove the α service module of the Orion central module and dock with the crystal module, the second one to remove is the β service module, which will dock with the hope module, and finally γ the service module to dock with the discovery module!" ”

The old cat's toes move across the screen, and the touchscreen display gives the butt results.

According to the old cat's plan, after the renovation is completed, the number of cabins on the joint space station will increase to nine.

"Why are all Orion segments codenamed? Don't they have names? Tang Yue asked.

"Absolutely." The old cat glanced at him, "It's just that I forgot." ”

"What about the airlock room?"

"There is no doubt that the airlock chamber should be removed before docking." The old cat looked at Mai Dong, "This requires a long and extremely heavy amount of extravehicular work, Miss Mai Dong." ”

"Hmm." Mai Dong nodded.

"We have to hurry." The old cat held the monitor in his arms, "The remaining four cabins on Orion are all inflatable cabins, and we have to empty and pressurize these four inflatable cabins and tie them to the shell of the Eagle lander." ”

"Use it as a cushion airbag."

"Yes, as an airbag when the lander lands." The old cat nodded, "At this point, only the command module of Orion 2 will be left, and the command module will be responsible for the control and communication tasks during landing......"

"Old cat, it's red again!"

"Change."

"The current angle of attack is 12 degrees, 37 minutes and 55 seconds, and then one second lesser?"

"Minus!"

"Data overflow."

"Smash!"

Once the modification of the Orion spacecraft officially began, the manpower was immediately insufficient, the HP computers in the Kunlun station and the system computers on the space station were running at full capacity, and every monitor in front of Tang Yue was jumping with charts and data, and he was copying paper and pen in his hand, remembering densely.

The old cat paced around Kunlun Station, like a feline with zoo syndrome.

"Old cat, the results of the first prediction of the impact point of the Toat comet are out!" Tang Yue stood up and raised the scratch paper in his hand.

The telescope on the space station finally collected enough data, and the workstation made calculations based on the observations to make preliminary predictions over long distances spanning up to one astronomical unit.

"It's going to crash into the Northern Hemisphere." Tang Yue said.

"Nonsense." The old cat pulled over a chair and turned on the computer's prediction results, the graphical simulation results were very intuitive, colorful topographic maps, red is the plateau, blue is the plain, and there is a large flickering red circle on the surface of Mars, which is very dazzling.

"This is the range of possible landing points for the comet, and with all the data collected so far, the computer can only be accurate to this extent." Tang Yue expanded the map of Mars and enlarged it, and the workstation marked the area where the comet Toat-Tang-ai could hit the surface, which is a very large oblate ellipse, with a semi-major axis of more than 3,000 kilometers, and the detailed latitude and longitude of the center of the ellipse is 18°N, 45°E.

The old cat groaned for a long time.

"This area is so broad and rough that it covers almost half of the Arabian Heights (Arabia Terra) and the whole of the Sabah Sea Highlands (Sabaea Terra)." The old cat pointed to the map, "You see, we are located in the Ihisi Plain, and to the west of us is the huge Sabah Sea Highlands, you must know that its width is 4,700 kilometers, and the Sabah Sea Highlands are further west is the Arabian Highlands, and its east-west length is also 3,000 kilometers.

The center of this ellipse is located in the middle of the Basha Sea Highlands, but its semi-major axis is 3,000 kilometers, that is, this area of more than 28 million square kilometers is a possible landing point for Comet Toat-Tang-Ai, and the comet may fall anywhere in this ellipse. ”

Tang Yue stared at the big red circle for a long time, and then stretched out his hand and pointed to the small plain on the map, which was also within the range of this big circle, which meant that the comet was also likely to hit the top of Kunlun Station.

"Kunlun Station is also in this circle."

"The area of the Ihidi Plain is too small, and we don't want to look at the probability that a comet will hit the Ihidi Plain...... The center of the forecast area is 2,500 kilometers from the Kunlun station, and I said that the impact of the comet will destroy everything within a radius of 2,500 kilometers, and if it falls exactly at the point of 18°N, 45°E, then the Kunlun station will be destroyed just right. The old cat's voice was low, "The vitality of Kunlun Station lies in ...... Whether the distance between us and the point of impact is greater than two and a half thousand kilometers. ”

"In other words, if the comet falls to the west of the center of the ellipse, Kunlun Station will be able to escape." Tang Yue said.

The old cat nodded, "If it falls to the east of the center, then the distance between Kunlun Station and the impact point will be less than two thousand five hundred kilometers, and everything will be over." ”

"A 1 in 2 probability?"

The old cat nodded slowly, "Roughly speaking, it's a 1 in 2 probability." ”

Tang Yue raised his head and took a deep breath, "So, there is a circle of heavenly damnation above the head of Kunlun Station, we have to see which way this circle shrinks next, if it shrinks to the west, then Kunlun Station will be safe, if it shrinks to the east, then we will be involved in a disaster that destroys the world and destroys the world." ”

"That's right, that's what it means, continue to collect observational data." The old cat pressed Tang Yue's shoulder, "We have to see which way it is going to shrink in a circle." ”