Dead on Mars

Chapter 68 - Sol Ninety-Nine, Saving the World with a Shovel
The next day at dawn, Tomcat drove the Mars Wanderer out and stopped by the side of the Eagle.

Donning the Radiant Armor, Tang Yue stood on the sand and looked up at the tall lander’s Descent Vehicle. Even though the Ascent Vehicle had been launched, the Eagle remained the tallest and most striking object around Kunlun Station.

Tang Yue circled the lander a few times. The, originally white, paint had been scorched black by the rocket engine, and beneath his feet was a layer of sand that was orange-red in color—a signal that they were rich in hematite. Beneath the sand was hard basalt. Mars was a nearly-dead planet, and any seismic activity had died down ages ago. These ancient rocks had been formed three billion years ago. Under the years of weathering, they had turned to sand followed by dust.

Tomcat pushed open the rover’s door and jumped down from the driving compartment.

Tang Yue gently knocked on the lander’s hard shell. “How much propellant is there left in here?”

“There should be some left. There’s redundancy for the propellant in the Descent Vehicle’s engine, so it’s unlikely all of that was burned up.” Tomcat stood akimbo as it looked to size up the Eagle. “However, we will need to open it up to know exactly how much is left.”

The Eagle’s Descent Vehicle had Raptor 3C rocket engines. They used methane and liquid oxygen as a propellant. And even middle school students knew that methane and oxygen burned to produce carbon dioxide and water. One mole of methane and two moles of oxygen reacted to form one mole of carbon dioxide and two moles of water. It was an excellent source of fresh water.

This was Tang Yue’s plan—obtain fresh water by mixing the propellant in the lander.

OId Cat returned to Kunlun Station and brought back a toolbox.

The Descent Vehicle didn’t have an accommodation ladder, so Tomcat could only use the Mars Wanderer as a ladder. It climbed on top of the Mars Wanderer and came close to the Eagle’s outer shell while wrenches and screwdrivers hung from it.

Even though it sounded simple, obtaining the methane and liquid oxygen from the propellant reservoir wasn’t an easy task. They couldn’t smash open the reservoir to release the fuel as methane and liquid oxygen would completely leak out in a short span of time. The only way was to create a conduit with a decompression valve. The methane and oxygen, that were in a liquid state inside the reservoir, were constantly evaporating so without the decompression valve the reservoir’s pressure would reach dangerous levels.

In order to successfully use the lander’s fuel, the methane and oxygen needed to be channeled slowly and safely to a reservoir before they were burned.

This was a very complicated task for Tomcat and Tang Yue. Firstly, they needed to remove the lander’s fairing.

Such intricate work was difficult for the Radiant Armor-clad Tang Yue, so he could only leave it to Tomcat.

Tomcat held a screwdriver in its mouth as it opened the lander’s service access. It narrowed its eyes before finding the pressure gauge.

“How is it?” Tang Yue asked from below. “How much propellant is left?”

“Hmm… Slightly lower than I expected. It might be because the propellant is constantly evaporating. We still have about 200 kilograms of methane.” Tomcat frowned. “This much methane will at most produce 400–500 kilograms of water. However, this much water should be sufficient to plant tomatoes and carrots.”

“Can this water be added to the water tank?” Tang Yue asked.

“No.” Tomcat shook its head. “This water isn’t potable before it’s processed and purified… However, how do you plan on collecting this water? The combustion of methane and liquid oxygen is steam.”

“Don’t worry. Leave the collection to me.”

Tang Yue was confident.

At two in the afternoon, Tomcat removed the lander’s fairing, exposing the entire propellant reservoir and the rocket engine. Immediately following that, they began preparing the modification plans. Tang Yue got two rubber tubings and a Y-shaped glass tube from the Kunlun Station. These items were used in experiments previously by the research team and had already been stored away by Tang Yue.

Tomcat attached the rubber tubing to the propellant reservoir’s decompression valve—one for the methane and one for the oxygen. Iron wires were used to tie them tight to prevent any leaks.

“OK!” Tomcat stood on the Mars Wanderer and waved its paw.

Tang Yue stood below, picked up the two rubber tubings and connected them to the two ends of the Y-shaped glass tube, before fastening them with iron wiring. In time, the methane and oxygen would burn within the glass tube, producing carbon dioxide and steam.

Tang Yue felt as if he was back in high school doing chemistry experiments.

“OK!” Tang Yue signaled by raising his hand. “Tomcat, you can give it a try!”

Tomcat nodded. Using a wrench, it slowly twisted the valve, allowing one mole of methane and two moles of oxygen to react. To prevent any wastage, and to ensure that the methane burned up completely, Tomcat had to carefully control the flow of methane and oxygen. It stared at the pressure gauge with a serious expression.

“Watch it—!” Tomcat warned. “I’m about to turn the valve!”

Tang Yue took out an electric arc igniter and moved it close to the glass tube. With a spattering sound, he lit the methane.

A small yellow flame flickered at the end of the glass tube as high-temperature steam met the cold weather outside, immediately condensing to form small liquid droplets and white mist. Through the thick glass visor, he observed the burning methane and exhaled.

They had obtained their source of water.

“Tomcat! We succeeded!”

…

Tomcat and Tang Yue stood on the sand, their heads looking down at the glass tube.

After many experiments, they had finally determined that the methane in the lander could be safely combusted—it wouldn’t suddenly blast them to kingdom come.

The next problem was to efficiently gather the resulting steam from the combustion.

“You said you have a method to collect the steam,” Tomcat said. “What’s the method? I have to warn you ahead of time that we don’t have condensate tubes. All the large experimental apparatus have either been damaged or taken away. We can’t even find a long enough glass tube to use as a condensate tube.”

“We don’t need a condensate tube. It’s too slow.” Tang Yue shook his head. “Using such a thin glass tube to collect four hundred kilograms of water will take us a year.”

Tang Yue really didn’t plan on using the usual condensate tube to collect the water. Such a method was common in a laboratory, but it wasn’t convenient doing so on Mars with sand blowing everywhere. Glass was too brittle, and a long glass tube was even worse. Furthermore, a condensate tube’s collection speed was too slow. If they tried to speed it up, it would easily create waste.

“Then, what method do you plan on using?” Tomcat asked.

Tang Yue turned to return to the garage. A few minutes later, he returned with a long shovel.

Tang Yue threw a shovel to Tomcat.

Tomcat held it and looked at it blankly.

“Shovel?”

Using a shovel to collect water?

“That’s right!” Tang Yue nodded. He waved the shovel in his hand. “We will use shovels to collect water!”