65 million years ago, Tower Island, Earth
3D brain scans of Cynthia and her companions appeared before Maria and Tesla. Nearby, Brahma and his wife waited anxiously for Maria's analysis.
"The folds in their brains, the number of neurons, and the structure of their neural networks all look normal. Why are their minds incompatible with our computers, making it impossible to upload them?" Maria asked, baffled.
"Looks like analysis alone won't give us the answer. Let's just try connecting them to the system," Tesla said.
Hope flickered in Vinu's eyes, then faded. She said timidly, "Under the laws of the Venus Alliance, Cynthia and the others aren't legal citizens, so they don't have the right to upload their minds."
Nikola Tesla exchanged a look with Maria, then said loudly and resolutely, "Brahma volunteered to guard the space elevator landing site. He'll face isolation and danger. That alone makes your daughter Cynthia more than qualified to upload her mind."
Maria added, "Besides, all the laws of the Venus Alliance will become invalid starting January 1 next year. If it's technically possible, there'll be no legal obstacle to extracting Cynthia and the others' genes and uploading their minds."
The experiment to merge clone Cynthia's mind with a computer began.
The connection wouldn't establish. The computer didn't respond, but Cynthia reacted violently. After she raised her hand to indicate that she felt unwell and they disconnected her, her blood pressure rose and she struggled to breathe, doubling over as she coughed repeatedly.
Vinu patted Cynthia's back with a mix of grief and tenderness, looking at Maria with pleading eyes. Maria and Tesla didn't know what to say. They simply shook their heads in silence.
Wiping the tears from the corners of her eyes, Vinu asked Tesla, "Tell me, when Mars explodes, will we have any chance of surviving here?"
Tesla explained that, according to his plan, when Mars exploded, Earth would be 120 degrees ahead of Mars along its orbit. Most of the rocks and ice produced by the explosion would fly toward the trailing and outer sides of Mars's orbit, forming an asteroid belt between Mars and Jupiter.
A tiny amount of debris would fly toward Earth. Even if some of it struck the planet, the impact sites would be in the MAYA region, behind the Tower Island power station.
The mass of the impacting debris would be negligible compared with the entire Earth. It wouldn't affect Earth's orbit or rotation speed, nor would it directly strike the superluminal wave power stations at Tower Island and Victoria.
But that didn't mean the impacts would have little effect on Earth. Quite the opposite: the vast clouds of dust they produced would blot out the sky, and their tremendous kinetic energy would cause powerful earthquakes and volcanic eruptions in many places.
Toxic gases mixed with the dust would envelop Earth's atmosphere, and the whole sky would seem to be ablaze. All life exposed on the surface, including the dinosaurs, would die for lack of sunlight and oxygen.
Maria asked Tesla, "Before Mars explodes, can we take Vinu and Cynthia and the others with us to hide on Saturn?"
Tesla said with a troubled expression that there were too many clones. Taking only Vinu and Cynthia would be unfair and irresponsible, but their current spacecraft simply couldn't carry all the clones. The rest would have to stay on Earth.
"Nikola, could we build a safe house for Vinu and Cynthia and the others? Food and water won't be a problem. Couldn't we use oxygen generators to supply them with oxygen?"
"Brahma's about to take up his post at the Victoria Power Station, and the space elevator was expensive to build and has a sturdy structure. It can also generate power. But this so-called power station on Tower Island is different. It was built to receive superluminal wave energy, channel it into Earth's core, and reshape the terrain. It has no generators."
Everyone looked at Tesla in confusion, as though asking, "So what?"
"The special-fuel power stations we use now will be destroyed. Without electricity in the Tower Island region, they won't be able to use oxygen equipment," Tesla said. "We can't settle Vinu and Cynthia and the others in the Victoria region and have them share Brahma's power station, because it's dangerous there. If invaders arrive, Brahma may destroy the station."
As she worried about Vinu and Cynthia, Maria thought of Brahma too. She asked in confusion, "Nikola, if we know the invaders are coming, why don't we destroy the space elevator now? Then Brahma wouldn't have to guard such a dangerous place."
Tesla shook his head. "The equipment at Victoria is both a space elevator and a superluminal wave power station. Some of the heat energy it receives is being injected underground. That energy is far less than what's being injected here on Tower Island, but it still plays a major role in reshaping the terrain. We can't stop it yet."
Tesla calculated silently, then added, "The invaders are people too. They'll wait until Earth's atmosphere has settled and the oxygen levels are suitable for survival before coming down to the surface. I estimate it'll take at least 30 years. The energy injected into Earth during those 30 years will continue reshaping the terrain for a long time, making it more suitable for us to survive in the future."
"I understand. The Victoria region will develop a Great Rift Valley and lakes, and become the source of rivers. Diverse plants and animals will spring up in abundance."
"Looks like Vinu and Cynthia and the others will have to keep living in the Tower Island region without a power supply. Earth's atmosphere and natural ecosystems will take an extremely long time to recover. Relying on stored oxygen tanks to supply hundreds of clones for decades or even centuries isn't feasible."
Nikola Tesla realized that toxic gases would contaminate the air, but water was rich in pure oxygen. Without electricity, chemical agents could be used to extract oxygen from the water and supply the clones in a relatively sealed space.
Nikola Tesla's solution was to make use of the Tower Island region's abundant natural caves and find a suitable large cavern deep underground.
An underground river could provide drinking water and, with special equipment and chemical agents, a supply of oxygen. Food could be stored, poultry and cattle and sheep could be raised, and fish could be added to the menu. Food shouldn't be a problem.
At last, a smile appeared on Maria's face. "You really are a genius. The oral medication I developed for gene-recombination sequencing will come in handy too. It can't grant eternal life, but it can keep people youthful and vigorous for decades, even centuries."
As if by magic, Maria produced a box of corn seeds. "These are seeds I carefully improved. The plants will grow ten meters tall, and they're nutritious and high-yielding. They can be used for food and animal feed."
Vinu looked relieved. Brahma seemed even happier than she was, and the couple thanked them again and again.
Vinu suddenly remembered an important question and asked Tesla:
"After Mars explodes, how long will it take you and Maria to return to Earth and meet up with us? Will we have to wait for many years?"
This seemingly simple question stumped Tesla. Mars would explode, and Earth would be wrapped in dust. Nothing like that had ever happened before. How long would it take for Earth's natural environment to recover? Tesla didn't know. He connected to the Lightning Ball and asked the external brain.
The external brain's answer was scientifically sound but left them speechless. The time it took for Earth's atmosphere to settle depended on the size and composition of the impacting object, as well as its speed and angle of impact. Without specific parameters, it was impossible to estimate the settling time accurately. The conclusion was that it could take decades—or thousands of years.
For Tesla, or even humanity from Venus as a whole, waiting decades or a century was manageable. A thousand years or more wasn't, because the gene medication developed by Maria and the other life-science researchers on Venus could only ensure that Venusians lived to the age of 500.
"When Dean Abbott and I drew up the Mars explosion plan, we estimated the most probable mass and kinetic energy of the Martian fragments that would hit Earth. We projected that it would take 50 to 300 years for Earth's atmosphere to settle accordingly," Tesla said.
"Ah? That long? Looks like I'll need a huge blackboard. I'll mark it once a day and hope you come back as soon as possible," Vinu said with a wry smile.
Tesla pondered for a moment, then took out some paper and a pen. He drew three circles—large, medium, and small. The large and medium circles touched, and their graduations meshed like gears. The small circle sat inside the medium one, touching both of them at the point where the large and medium circles met.
Vinu, who had worked as an accountant, noticed that the large circle had 365 graduations, the medium one had 20, and the small one had only 13.
"What do these circles and their graduations mean?" Maria asked curiously.
"I'll make Vinu three circles to use as a handmade calendar. Then she won't need that huge blackboard she mentioned," Tesla explained.
When Mars exploded, Earth would lie 120 degrees ahead of it in its orbit, or one-third of the way around a 360-degree circle. The conjunction cycle between Venus and Earth was 584 days, and the conjunction cycle between Mars and Earth was 780 days. If a year on Earth was counted as 365 days, the least common multiple of these three numbers was 113,880 days, or about 312 years.
If they made a manual device with graduated rings, for example, with every point of intersection corresponding to a certain number of days, then representing 113,880 days would require rings with too many graduations, making them difficult to make and use for keeping track of time.
But if they set the total number of days as 365 × 260 = 18,980, one-sixth of 113,880 days, that would give them an exceptionally interesting and useful calendar cycle. This number of days was divisible by 365, by 584 when multiplied by 2, and by 780 when multiplied by 3.
What did it mean for a number to be divisible by a conjunction cycle? It meant that two planets in conjunction would be aligned with the Sun. Dividing 18,980 by the 780-day conjunction cycle of Mars and Earth didn't give a whole number, since 780 = 3 × 260. While 18,980 was divisible by 260, it wasn't divisible by 3.
After Mars exploded, Earth would lie 120 degrees ahead of Mars along its orbit, equivalent to one-third of the way around the conjunction line. After 18,980 days, Earth and Mars wouldn't have completed a whole number of conjunction cycles. Instead, they would have completed a whole number of cycles plus two-thirds of a cycle, and with their initial position at one-third of a cycle, Earth and Mars would end up aligned with the Sun—truly in conjunction.
When Tesla and Maria returned to Earth from Mars in their spacecraft, they could use Mars's gravitational slingshot effect to accelerate and save fuel, provided Mars and Earth were in conjunction.
So, within the 50-to-300-year period, the ideal return window would recur every 18,980 days, or every whole-number multiple of 52 Earth years of 365 days.
"So every 52 years could be a chance for you to return, right?" Brahma and Vinu asked in unison.
"That's right. The greatest common divisor of 365 and the product of the medium and small circles, 260, is 5. If you divide the large circle by 5, you can match 73 graduations to 260. Or, if you divide the medium circle by 5, you can match 52 graduations to 365. Either way, the product is 18,980."
"What an unusual calendar! It's based on the conjunction cycles of Earth, Venus, and Mars, and 18,980 days is just 52 years of 365 days. Give this calendar a name," Maria said.
"Let's call it the Short Calendar," Tesla said, thinking of Jupiter and Saturn, whose orbital periods were longer.
A stitched poem for the chapter:
The world is an inn for travelers, Song, Xue Jixuan
Rain-washed, they meet in lush green again. Yuan, Fan Cheng
Alone, I calculate the journey home. Qing, Zhao Guanbin
Who could have hoped to meet among the stars? Ming, Luo Hongxian
Before you continue