Dead on Mars

Tang Yue unbuckled his seatbelt and stuffed the photo frame on the dashboard into his pocket. Following that, he hopped off the Mars Wanderer’s driving compartment with Tomcat waiting down below to hold his hand in the darkness. With the weather they were facing, they couldn’t afford to lose each other. However, they didn’t use a safety rope to tether themselves together. Tomcat could only hold Tang Yue tight.

Tomcat’s paw held the small emergency light as he waved it in front of Tang Yue. “Follow me closely! Tang Yue, can you hear me?”

Even though the man and cat were inches apart, the quality of the radio comms was suffering terribly. The large amounts of dust and static suspended in midair interfered with the radio signals.

“I copy you.” Tang Yue nodded. “Loud and clear!”

“We are only 3.5 kilometers from our destination. It’s in that direction… We need to walk straight in that direction for 3,500 meters.” Tomcat stretched out its paw and pointed ahead. “How are you? How’s the Radiant Armor? How much oxygen and power do you have left?”

“I’m good. I had a filling breakfast and am filled with energy.” Tang Yue brushed away the sand and dust from the display terminal on the Radiant Armor, allowing its faint blue light to show. “The Radiant Armor’s internal pressure is normal. The EOG still has ten hours left. The EVA’s batteries can last another six hours.”

“Good.” Tomcat nodded. “I’ll walk ahead. You take my six. Put your arms on my shoulder.”

Tang Yue placed his hands on Tomcat’s shoulders, taking one step whenever Tomcat took one. He moved his left foot when Tomcat moved its left foot, likewise for the right foot. It was like the zombies of legend in the Qing dynasty.

To cover 3,500 meters in six hours would have been a piece of cake for Tang Yue under normal conditions. He could probably cover that distance hopping on one leg in six hours.

However, the sandstorm made things a lot more complicated.

To them, the distance was a secondary concern. The greatest problem was the determination of their direction. If they ended up getting lost, the time they wasted in the sandstorm would be greatly extended.

“Humans are unable to strictly guarantee a straight line with their footsteps, which is why you need sight to correct your path. In darkness without any references, you will only walk in circles,” Tomcat said. “Many a time, you might believe that you are walking straight, but you might be deviating from the correct direction without realizing it.”

“Coriolis force?” Tang Yue looked down, taking steps with his eyes closed. His tottering steps resembled an emperor penguin’s steps. Since he couldn’t see anything, Tang Yue decided to close his eyes, leaving the navigation completely to Tomcat. He was like a blind man with his guide dog.

“The Coriolis force is just one of the reasons. The main reason is that humans aren’t able to guarantee that each stride is identical.” Tomcat wore an IVA suit and walked equally carefully. Without the light’s illumination, even its night vision was useless. Tomcat could only grope its way forward. “Most people have stronger right legs, so their right stride is often bigger than their left. This difference is extremely tiny, and you wouldn’t notice it usually, but when covering long distances on a desert, this tiny difference would cause you to deviate left without you realizing it. Eventually, you would complete a huge circle and return to your starting point.”

“So your left and right strides are the same?” Tang Yue asked

“Yes,” Tomcat replied. “It’s strictly set to be 0.4 meters.”

“You sure have short legs.”

Tomcat led Tang Yue forward, leaving deep footprints in the thick layer of drifting sand that probably reached Tang Yue’s ankles. When he turned his head again, he could no longer see the Mars Wanderer. The old dog had vanished into the darkness and Tang Yue knew that there was no chance of meeting it ever again.

While Tang Yue tightly gripped Tomcat’s shoulder, it couldn’t see its back. All he could see was the light in its paw. Tomcat had raised the small emergency light above its head, making it the only source of light in the hurricane.

Tomcat suddenly stopped.

Tang Yue came to a halt as well. “What’s wrong?”

“I need to determine if I’ve deviated.” Tomcat stood in its spot. “I’m blind just like you. If I just walk without any corrections, we will deviate all the way to the south pole.”

“But you have a map inside your brain.”

“A map needs something to reference to be of use.” Tomcat slowly crouched down, grabbing a handful of sand. “Tang Yue, did you notice? The drifting sand at our feet is thickening.”

Tang Yue crouched down. The sand which reached his ankles had now reached his calves.

“What does this imply?”

“It implies that we are leaving the Isidis Planitia,” Tomcat replied. “The terrain is undergoing obvious changes.”

“Does this mean we are walking in the correct direction?”

“No, no matter which direction we take, we will be leaving the Isidis Planitia… Alright, we can continue walking. I’ve figured out where we are.” Tomcat straightened its body and said a string of numbers. “130.8, 158.4.”

“130.8? 158.4? What’s that?”

“Our current coordinates. I’ve set the Mars Wanderer’s location as the origin and set up a Cartesian coordinate system. I just told you that a step is 0.4 meters, so every step you take is 0.4 meters,” Tomcat explained. From the moment we set off, I’ve already taken 512 steps, a total of 204 meters.”

“Then where’s our destination?”

“Its coordinates are approximately (2498.2, 2506.6).”

“Is it accurate?”

“That’s the best I can do.” Tomcat shrugged. “There will always be accumulated errors from inertial navigation.”

Every five minutes, Tomcat would stop to get their bearings. Its stride could, in theory, guarantee that it was walking straight. However, the reality was far more complicated than theory. The undulating terrain and obstacles would force Tomcat to circle around from time to time.

Tang Yue also kept a mental count. He followed Tomcat with his eyes closed, incrementing the counter with every step he took. However, this counter always hit a snag at a certain number—perhaps a result of encountering a boulder or ditch. When that happened, Tomcat would turn its head to warn him. It would then think of means to circle the obstacle. And by the time all of that was done, Tang Yue would have lost count of his steps.

In the dark world, he couldn’t even sense himself advancing. He had lost count of his steps, causing him to lose a sense of distance.

“Tired?”

“I’m alright.” Tang Yue panted. “How far have we walked?”

“Six hundred meters.”

“Only six hundred meters?” Tang Yue was somewhat surprised.

“Yes.”

“I felt as though we’d already walked six kilometers,” Tang Yue said. “Strange… Why do I feel so tired despite such a short distance?”

“Mental stress,” Tomcat said. “When ordinary people completely lose their vision, they will suffer considerable mental stress. You aren’t a blind person, so it’s difficult for you to get used to this state in such a short period of time.”

The sand at their feet was piling up. When going upslope, Tomcat and Tang Yue would be sliding downwards. When they crawled up a high sand dune, the higher they went, the steeper it was. Towards the end, this man and cat had no choice but to use all their limbs to proceed forward. Tang Yue would grab Tomcat by its hind legs as he crawled up the sand dune, his four limbs sinking deep into the sand.

It was extremely inconvenient walking on drifting sand. There wasn’t anything for them to exert their strength against. No matter how Tang Yue opened up his stride, he was walking on the spot. Sand would flow away from him as if he was having swimming lessons as a beginner. Tomcat wasn’t in a much better state. It was struggling in front of Tang Yue. And when it took three steps forward with great difficulty, it would slide back to its original spot, tumbling into Tang Yue.

Tang Yue grabbed it as they slumped onto the sand, panting.

“Are you okay?” Tang Yue’s visor made contact with Tomcat’s helmet. He switched on the Radiant Armor’s internal lights, illuminating his face. “Were you damaged?”

“No. Just a system breakdown,” Tomcat said. “My left arm was disobeying my commands and couldn’t exert any strength… This arm of mine is about to expire.”

“How’s your current state?” Tang Yue knew that Tomcat had an old injury in its left arm. The problems kept showing itself during their trip and the symptoms seemed to worsen.

Tomcat tried moving its limbs and after thinking for a few seconds, it shook its head. “Not too optimistic. The four limbs are stiff. I’ve stayed too long in the hurricane. I’m suffering from stiff joints due to the low temperatures.”

“Then shall we take a break?”

“No, the more we drag this out, the worse it becomes. I might need some heating to raise my internal temperatures,” Tomcat said. “But we clearly lack those conditions.”

Trying to raise temperatures was an impossibility. What they lacked most was electrical power. Tang Yue’s Radiant Armor had heat insulation and heating capabilities, but Tomcat’s IVA suit didn’t have that. The IVA suit it wore was only to shield it from the sand. It didn’t even have a battery in it.

Tang Yue fell silent for a moment. “Listen, Tang Yue. If you have to go it alone…”

“Shut up.” Tang Yue cut it off. “I’ll teach you how to raise your temperature. Do you know how friction generates heat? Mechanically convert it into potential energy. Yes, rub your paws. When we are outside during winter, we rub our hands to gain warmth. As for Old Wang and Thomp, they would rub their naked arms against each other for warmth, making you think they were gay… Now, begin rubbing your paws! Rub! Rub as hard as you can!”

Tomcat was taken aback.

“As for traveling, I’ll do the thinking. Don’t even think of having me abandon you here…” Tang Yue bent down to pull on Tomcat’s forelimbs. He wrapped them about his shoulders and neck and with a low grunt, lifted it up. Finally, using all his remaining strength, he straightened his body, tottering to an upright position. “Don’t even think of having me abandon you here! Don’t even think of it… If you can’t move, I’ll carry you!”