Tang Yue pulled the cart and dragged the solar panels through the battery farm.

The extreme drought on Mars makes it difficult to find a place on Earth that can be compared to here, and the Ihidi Plain, where Tang Yue is located, has not had a single rain in the past tens of millions of years, and going back to the same time, the Sahara Desert on Earth was still a rain-rich tropical rainforest at that time.

The vast majority of water on Mars is frozen at the poles at low temperatures, and in those low-lying canyons where sunlight is difficult to reach, the permafrost containing water will not be civilized for hundreds of millions of years, which is a very large water resource, with a total amount of more than one trillion tons, and if humans want to colonize Mars in the future, then it will be an important source of fresh water.

Speaking of which, there are a lot of resources on Mars, including water and methane, but it's a pity that human hands are too short to reach.

Tang Yue pulled open the bracket, propped up the battery board, grabbed a handful of soil, and gently crushed it and scattered it under his feet.

It stands to reason that the soil contains a trace amount of water, and the old cat said that as long as you set up a pot that is large enough, dig deep into the soil and heat it, you can get water vapor...... The reason why this seemingly infinite method of preparing fresh water was not really implemented was because Tang Yue really couldn't find such a big pot and couldn't collect such a thin water vapor.

"Whether it is rainfall or typhoons on the earth, including ocean currents and atmospheric circulation, the root of it is the flow and exchange of heat." "The warm currents in the ocean rise, the cold currents sink, the water vapor carries the heat into the atmosphere, and then releases it through the low-pressure cyclone, the complex water system circulation on the earth, the engine behind it is heat, but Mars is dead, it has no shortage of water, it lacks the engine to drive it all." ”

"Is there a way to get this engine running again?" Tang Yue asked casually.

"The engine of Mars is itself, but this engine has been out of operation for more than three billion years." The old cat replied, "You want to get Mars running again?" Human beings can't do it, and this is a God's project. ”

"I'm reminded of the magnetic stirrer I used in chemistry class in college, have you ever seen anything like that, old cat?" Tang Yue said, "A spindle-shaped metal bump, throw it into the solution, as long as you apply an external magnetic field to it, then this stirrer will spin rapidly, the same reason, if we apply a strong enough external magnetic field to Mars, can we re-drive the Martian core?" ”

"Once the geological activity of Mars resumes, then the gas in the mantle and poles will be released, and the atmospheric concentration will gradually increase." Tang Yue continued, "The environment of Mars has been improved. ”

"The core of Mars is a big lump of iron with a radius of 1,800 kilometers." The old cat said, "It weighs at least 1.9×10∧20 tons, and it weighs 1.9 trillion trillion tons. ”

"With this ability, you can all colonize the galaxy, and you still have to think about Mars." The old cat finally said, "Don't be delusional, even if there are thousands of possibilities to bring Mars back to life, it is impossible to do it now." ”

Tang Yue held a shovel with a long handle in his hand and wrote stroke by stroke on the sand at his feet.

"Don Yue came here for a visit."

"Human civilization is here."

"Earth creatures come here for a visit."

"Later intelligent beings, if you see these words, remember that someone has been here before you."

The sharp tip of the shovel cut through the sand, dragging a deep gully, but the free grains of sand immediately flowed back into it, filling the sunken ground.

The words written by Tang Yue quickly became blurred.

Tang Yue threw the shovel on the ground, sat down to rest, just two minutes of effort, the two words "Tang Yue" can no longer be distinguished, this is the erosion of the traces of civilization by the forces of nature, the blurred handwriting of quicksand is just a small microcosm, Tang Yue dug a ten-centimeter-deep ravine, and it took ten minutes for nature to smooth it, and Tang Yue dug a ten-meter-deep pit, then it took 100,000 years for nature to smooth it.

Tang Yue wanted to leave something behind, but the more he thought about it, the more he could feel the difficulty of this matter.

Time is a bulldozer that slowly and unstoppably bulldozes everything out.

After all, the best carrier for recording civilization is civilization itself.

"Where did that comet go? How far are we from it? Tang Yue raised his head and looked up at the sky.

"Forty days."

The old cat replied that it was working in a hurry.

"What about the comet's orbit?"

"It's still counting...... Hell it's crashing again, HP's computer is of this quality? I shouldn't have set so many variables, Miss Maidon? Miss Mai Dong, do me a favor! ”

Tang Yue listened to the old cat and Mai Dong arguing in the channel, the re-entry of the Orion 2 spacecraft into the atmosphere was much more risky than the original launch of the Eagle spacecraft, and the old cat himself said that if it was not forced to hurry, it would definitely not let Mai Dong board this wrecked ship that must be sunk.

The dog can jump off the wall when he is in a hurry.

Cats will curse when they are in a hurry.

Tang Yue packed up the battery board and returned to Kunlun Station.

“＊！ HP: Your broken computer! I'm *your whole family**! The old cat is frying, "I wish your whole family ** heaven!" Explode on the spot! ”

Tang Yue hung the Mingguang armor on the wall to charge, took off his clothes and put on his robe, poured a glass of water to drink, and the old cat took out a stick from under the table and threw it over, "Go on!" ”

"What is this?"

Tang Yue caught the long stick like a cane, the weight was quite heavy, he looked up and down, the length was about sixty centimeters, it was very hard to pinch, it had a metallic texture, it might be made of some metal bracket, and there was a layer of white manuscript paper wrapped on the outside, obviously the waste of the draft paper was used, and a circle of paper tubes was glued to the bottom of the pole, wrapped in layers of transparent tape.

"A scaled-down model of the Orion II spacecraft." The old cat replied.

"Orion...... Number two? Tang Yue grinned, he didn't find any similarities between this thing and the Orion spaceship, except that it was equally slender, it was better to say that it was a spaceship than a hammer, and it could be used upside down to smash people's brains.

"This is the main truss." The old cat pointed to the thin pole.

"It's the engine." The old cat pointed to the paper tube at the bottom end, the paper tube was sealed tightly with tape, Tang Yue didn't know what was inside, but the weight was very heavy.

Tang Yue nodded slowly, and as soon as the old cat reminded him, he could see it.

It is indeed an Orion model, although it is very abstract and impressionistic, and the level of craftsmanship of the old cat is really not flattering.

"It doesn't look like it, after all, the conditions are limited." "But in terms of weight ratio I did as close as I could, and you don't convince yourself to make a better one." ”

"Serve! Brother Cat's shot is extraordinary! ”

Tang Yue did not hesitate to give his thumb.

With the scaled-down model, the old cat finally no longer needs to use its pen to demonstrate, Tang Yue erected Orion II in the palm of his hand, and the model stood very steadily.

Tang Yue stretched out his index finger and gently pushed it.

"It's stable."

"Most of its mass is concentrated at the bottom end, which is why we have to dismantle the Orion and Eagle spacecraft, and we have to keep the center of gravity as low as possible." The old cat said, "The lower the center of gravity, the more stable and safe it is." ”

The old cat took the model off Tang Yue's palm and stood on the table.

"I'm working on the problem of attitude stability, it has to land vertically, and the margin for deviation from side to side is no more than five degrees, if one is not careful, this happens......" The old cat flicked lightly on the pole, and the Orion model fell on the table with a "clang", "then it's all over." ”8)