Mars, the "Bird's Nest" automated restaurant.

The TV on the restaurant wall is playing the old movie "The Martian," and the male lead, Matt Damon, is eating potatoes grown from his own poop.

"Everyone, let me make it clear first that I really don't mean to disgust you," Zhang Fan said while eating. "We might really be going to have to grow potatoes on Mars."

"Why grow potatoes?" Yui asked, her cheeks bulging from eating. "Aren't other foods tasty? I hate potatoes."

“They’re not for eating.” Zhang Fan sighed helplessly. “Liao Changtian said that potatoes are the simplest basic energy source we can currently obtain.”

"Ethanol?" Katerina, quick-witted as ever, immediately grasped the crux of the problem.

“Yes.” Zhang Fan nodded.

"Is the solar energy in the 'Bird's Nest' not enough?" Katerina asked curiously.

“That’s not what I meant.” Zhang Fan shook his head. “If it’s just to meet the needs of the ‘Bird’s Nest’, then solar energy is certainly enough.”

"But if it's used for 'opening up new mines', it's not enough."

"Open a branch mine?" Katerina's eyes widened this time as well.

“Yes, I’m not joking, I’m really not joking.” Zhang Fan made his expression serious as he spoke. “We’re going to start mining.”

As he spoke, Zhang Fan placed a book as thick as a brick on the dining table.

"This is what Liao Changtian has set for us to do in the coming year. You can simply think of it as something like a 'five-year plan' on Earth."

"What do you mean by 'we'?" Katerina asked, her eyes wide. "I want to be involved in this so-called plan?"

"Mhm." Zhang Fan nodded quickly. "There are only three of us on Mars, so the two of you are also invaluable labor."

"I don't want to!" Yui shook her head like a rattle. "I'm terrified of reading. This book is so thick, I'll die before I even finish it."

"No, no, no!" Zhang Fan shook his head repeatedly, immediately correcting Yui's mistaken idea. "This is not a 'book,' but a 'table of contents.' I printed it out to make it easier for you to find the contents of the book. The real book you are supposed to read is here."

Zhang Fan took out two 100TB USB flash drives and placed them on the table.

Yui fainted immediately.

...

Liao Changtian devised a plan for Zhang Fan that seemed almost impossible to complete.

The first phase of the plan is to mine helium-3 on Mars.

Helium-3 is a clean nuclear fusion material that does not produce harmful free neutrons during nuclear fusion reactions.

Mars has more helium-3 reserves on its surface than Earth. This is because Mars has only 0.6% of Earth's atmosphere and a weak magnetic field, allowing helium-3 brought by the solar wind to deposit on Mars.

To achieve the capability to mine helium-3 on Mars, Zhang Fan first needs to... grow potatoes, grow lots of potatoes.

Potatoes and helium-3, seemingly unrelated things, are connected in a strange way on Mars.

To develop helium-3, the first problem to solve is the energy issue of "mining" it. The solar panels on the Mars rover are insufficient to support the operation of the mining vehicle.

You can't just remove the solar panels from the "Bird's Nest" photovoltaic power station and move them to the mine. What would happen to the "Bird's Nest" then?

Lithium deuteride, used in fuel cells, is non-renewable; once used, it's gone, making it unsustainable.

Ethanol is currently the most suitable energy source.

Ethanol has a freezing point of -114°C, giving it excellent resistance to freezing, which is very important on Mars.

Ethanol combustion produces water and carbon dioxide, which, in the presence of a catalyst, can be converted into methane and oxygen. Both of these can be recycled and reused.

Starch is the raw material for industrial ethanol production.

Potatoes are rich in starch, easy to grow, high-yielding, and drought-resistant, unlike rice which requires a lot of water.

As the saying goes, women are in charge of the home, and men are in charge of external affairs.

Yui and Katerina were responsible for housework, while Zhang Fan was out mining.

Planting potatoes is actually not difficult; you just need to convert 5 out of 10 production chambers to produce potatoes.

Currently, there are four creatures in the "Bird's Nest": Zhang Fan, Yui, Katerina, and Bob. The output of the five production chambers is sufficient to supply their daily needs.

Of course, this would reduce the variety of food in automated restaurants and lower the quality of life, but we can't worry about that now.

Yui and Katerina usually grow potatoes at home, harvest potatoes, and produce ethanol.

Zhang Fan then drove a mining truck to mine.

The helium-3 mining site that Liao Changtian marked for Zhang Fan was more than 30 kilometers away from the "Bird's Nest".

Of course, this is not the only helium-3 deposit on Mars, but this deposit is the closest to the "Bird's Nest" and its helium-3 content is worth mining.

The mine cart can reach the mine site in one hour, but on the return trip, because it is fully loaded with ore, the mine cart can only travel at a speed of 10 kilometers per hour.

In other words, it takes 4 hours to make a round trip to the mine. Adding the time spent mining and loading, Zhang Fan leaves home in the morning and doesn't return to the "Bird's Nest" until evening.

The mineral deposit is located in the center of a crater. According to Liao Changtian, the crater's topography may have led to the accumulation of helium-3 at its base. The bulge at the base of the crater's center suggests that the crater may have been formed by an asteroid impact, and that the impacting asteroid likely contained abundant helium-3.

In short, just dig.

Zhang Fan felt that everything Liao Changtian said was nonsense, except for the last sentence, which was useful.

Clang—

Zhang Fan hammered a pickaxe into the rock on the ground, pried it open, and then used a shovel to shovel the loose rock into the iron bucket.

Once the bucket was full, he put down the shovel, picked up the bucket with both hands, and walked onto the back of the mine cart to dump the rocks inside.

Damn it! It's the 22nd century, why would I still have to do this grueling job as a human miner?

Is it really that difficult for you to attach a rock crusher or excavator shovel to the front of a mining cart?

Even on Earth, fully automated underground mining has long been achieved. Those black-hearted miners who braved dust and danger to dive into narrow and perilous mine shafts have long since become photographs displayed in Earth's museums.

But there's nothing we can do about it; mining on Mars is currently not cost-effective.

Although the "Bird's Nest" has a complete set of mineral mining and refining equipment, it is all for studying Martian geology and rock composition; no one has ever thought about large-scale mining on Mars. Therefore, from a cost perspective alone, using manpower to collect ores for research is the more reasonable approach.

Despite his complaints, Zhang Fan diligently and conscientiously loaded the ore onto the truck, one pickaxe and one shovel at a time.

When I get hungry at noon, I eat the bento boxes made by Yui, take a nap, and then continue working in the afternoon.

Mining in a spacesuit is no human endeavor, but fortunately, the low gravity on Mars significantly reduces the intensity of the work.

As the sun set, Zhang Fan filled the truck with ore and drove it back to the "Bird's Nest" base.

After pouring the ore into the smelting furnace, he didn't need to worry about the rest. "Xiao Feng" would take care of the rest, refining the ore into helium-3 bit by bit and storing it.

According to Liao Changtian, the content of helium-3 on Earth is 0.000137%, and the content on Mars is even higher. So if Zhang Fan is lucky enough, a whole day's work mining a truckload of ore could yield about the size of a soybean of helium-3.

Damn it!

After a long day, Zhang Fan took a shower and ate dinner, but he still had a daunting task ahead: tutoring Yui with her homework.

On Mars, Yui's foundation in space science was the weakest; of course, she wouldn't be much better off on Earth.

But there are only a few people on Mars, and Zhang Fan can't just abandon this important source of labor and let her do nothing all day.

So these days, Yui has been cramming on space-related knowledge in her spare time. Fortunately, Yui has also overcome her psychological barriers and is willing to work hard to learn.

After all, this was the only hope for saving Ivanka's sister.

In the evening, it's Zhang Fan's time to check homework.

"I asked you to draw a map of the Mars constellations, and this is how you drew it?" Zhang Fan was tired after a long day and was a little angry.

“That’s how it is.” Yui said, pulling her head down and looking miserable. “I followed the drawing that ‘Xiao Feng’ gave me. I carefully calculated the distances and proportions.”

"You still won't admit it?" Zhang Fan pointed to the Martian star system map drawn by Yui. "Then let me ask you, this one in the middle is Mars, this one is Phobos, this one is Deimos, and this smaller bright spot represents the Soyuz space station, right?"

"yes!"

"Then what is this point?" Zhang Fan moved his finger a long distance outward.

The planets immediately surrounding Mars are Earth and Jupiter; there are no other celestial bodies besides them.

"I don't know," Yui replied.

"You didn't know?" Zhang Fan was a little angry. "You didn't know and yet you drew it?"

"That's just how it is." Yui wanted to cry.

"Okay, okay, I won't say anything more to you." Zhang Fan quickly comforted her. "'Xiao Feng,' display the scanned images from the base radar on the big screen."

"The radar image is now displayed on the large screen."

"Yui, look." Zhang Fan pointed to the big screen. "We're on Mars. This is Phobos, this is Deimos, and this little dot is the Soyuz space station. Besides that, there's nothing else... anything else... huh?"

Zhang Fan's eyes widened.

A small bright spot appeared in space, which should have been empty.

"Xiaofeng! Use the base radar to scan the area at coordinates 253-443! Confirm if there is a radar reflection signal!"

"Scanning at coordinates 253-443 completed; radar echo received."

"Target location locked!"

"Target tracked and locked; currently located at position 252-442."

It's moving?!

Zhang Fan tensed up.

"Use the space telescopes on the Soyuz space station to acquire image data of the target."

"Target imagery is now displayed on the large screen."

Upon seeing the image on the big screen, Zhang Fan collapsed into his chair as if struck by a heavy blow.

"Fan-kun? What's wrong?" Yui asked anxiously as she helped Zhang Fan up.

The image on the screen was all too familiar to Zhang Fan; he came from there—

The Firebird Mars probe.