Gravitational lensing

The method for destroying the enemy's probe was straightforward. It involved using the same launch system designed for interstellar missiles, but instead of launching interstellar warheads, conventional high-explosive ammunition was used. Using hydrogen bombs for something so small would be overkill.

After calculating the trajectory, Xiao Yu aimed at the device and fired the ammunition.

Seventy seconds later, the high-explosive round traveled thousands of kilometers, directly encountering the alien civilization's probe. The pre-set detonator activated, and the ammunition exploded in mid-air, producing a flash of light. The probe spun out of control like a kite with a broken string, disappearing into the void.

Time was running out. Although this probe hadn't detected Xiao Yu, he couldn't be sure that the next one wouldn't spot him before he noticed it. It felt like a sword was constantly hanging over his head, ready to fall at any moment.

This sense of imminent threat was unsettling.

In the dark void of space, two civilizations were racing to locate each other. Whoever found the other first would gain a significant advantage, increasing their chances of victory by at least 30% in the subsequent clash.

The situation was not optimistic.

The enemy had already found an effective method, but Xiao Yu had yet to devise his own.

Releasing a swarm of probes to roam space randomly was a strategy the enemy could afford, but Xiao Yu could not. The reason was simple: to achieve effective signal coverage and to search such a vast area, an enormous number of probes would be needed. The enemy had a planet, which they could use as a material base to produce unlimited resources and build as many probes as they needed. Xiao Yu only had a fleet with limited resources and couldn't compete on the same scale.

Xiao Yu had to find another method to counter the enemy. Otherwise, he would have to rely on luck to avoid being discovered. But how long could luck last—one year, ten years, fifty years, a hundred years?

There were still several thousand years before reaching the Tianyuan Four star system. Even then, Xiao Yu couldn't guarantee victory upon arrival.

Xiao Yu continued his calculations under Chen Mo's watchful eyes, suppressing his despair and patiently working through his theories.

After countless failures and the passage of an unknown amount of time, Xiao Yu had destroyed at least ten more enemy probes.

Gradually, his eyes brightened.

Xiao Yu had come up with a method. It had passed the forty thousand testing barriers he had set up, proving its feasibility. Unlike the enemy's method, which involved some degree of luck, Xiao Yu's plan would eventually uncover the enemy as long as he invested the time.

Just as the enemy could use random probe searches, a method Xiao Yu couldn't employ, this method was one Xiao Yu could use, but the enemy could not.

This method involved gravitational lensing.

The concept of gravitational lensing was first proposed and predicted by the greatest scientist in human history, Einstein. Simply put, gravitational lensing occurs when starlight passes near a massive object, causing the light, which normally travels in a straight line, to bend due to the object's gravity. This makes the star's position appear slightly shifted.

Xiao Yu knew that the alien civilization's planet had a mass greater than Earth's. It was certain that gravitational lensing would occur around this planet.

However, on a cosmic scale, the planet's mass was still relatively small, meaning the gravitational lensing effect would be minimal. This implied that highly precise instruments would be required to observe which direction the gravitational lensing was occurring.

From there, it was simple: once Xiao Yu observed where gravitational lensing occurred, he could precisely calculate the enemy's position through a series of complex calculations.

This was why the method worked for Xiao Yu but not for the enemy. Xiao Yu's fleet, though massive, with a total mass of tens of millions of tons, was insignificant compared to a planet. Observing gravitational lensing caused by a planet was already difficult enough; detecting lensing caused by Xiao Yu's fleet would be impossible.

Xiao Yu estimated that only a civilization thousands of years ahead of his own could detect his fleet's gravitational lensing, and he was confident that the alien civilization he was dealing with didn't have this capability.

The original positions of celestial bodies were already recorded in Xiao Yu's Stellar Almanac. The current positions could be observed, and Xiao Yu's task was simple: re-observe all visible stars in the sky, then compare the results with the Almanac's data to see where starlight had shifted.

Although this sounded simple, it was a complex task requiring extremely precise observation instruments and enormous computational power.

Xiao Yu spent half a year preparing for this task.

Countless data were fed into the central computer, processed, and then compared with the original data from the Almanac. Star after star was ruled out by Xiao Yu.

Each star ruled out indicated that there were no signs of the enemy in that direction. Gradually, Xiao Yu's search area shrank.

In the past three months, Xiao Yu had narrowed the search from the full 360-degree sky to a region less than half that size, about 160 degrees.

The next star to be measured was a star in the constellation Canis Major, commonly known as Sirius.

Sirius is 500 light-years from the Sun, and there wasn't much detailed data on it from humanity's past. However, during the compilation of the Stellar Almanac, Xiao Yu had measured Sirius, collecting data on its mass, volume, spectral type, and more.

After re-observing Sirius, Xiao Yu began analyzing its data and comparing it to the original measurements.

"Hmm?" During the comparison, Xiao Yu noticed a very slight difference.

After accounting for errors due to his own movement, Sirius's position had shifted slightly from its original coordinates—by about one-millionth of a degree in right ascension and declination.

Xiao Yu immediately caught this signal and conducted a second review.

The recheck results came back quickly, and the conclusion remained unchanged. Sirius had indeed shifted slightly and inexplicably.

After ruling out all other possibilities, the only explanation left was that the alien planet was hiding somewhere between Xiao Yu and Sirius.

Xiao Yu felt a surge of excitement. Using Sirius as a center, he measured the surrounding stars, confirming that several had also shifted to varying degrees.

"Alright, I've finally found you," Xiao Yu muttered, his heart racing with excitement.

With this data in hand, it only took Xiao Yu thirty seconds to calculate the exact position of the alien planet.

They were located in the direction of Canis Major, about 32 million kilometers away from Xiao Yu.

"An eye for an eye—you send probes to find me, so I'll send hydrogen bombs your way. Just wait and see!"

Xiao Yu immediately prepared for the launch, firing a large-yield hydrogen bomb. It was expected to reach its target in three months and then detonate.

After more than a year of searching, Xiao Yu had finally found the enemy. A year's worth of suppressed anger burst forth, and Xiao Yu couldn't wait to see the explosion, eager to vent his frustration.

But Xiao Yu's actions were still under rational control. He intentionally waited ten days after launching the first hydrogen bomb before sending out the second batch, consisting of twenty hydrogen bombs.

Then, after five days of silence, Xiao Yu launched a third wave of twelve hydrogen bombs.

Xiao Yu deliberately kept his launch times and the number of bombs irregular to prevent the enemy from organizing effective interception methods. This way, the enemy would become increasingly paranoid, constantly fearing the next hydrogen bomb attack, living under the constant threat of annihilation. They would never know when the next bomb would arrive.

"Enjoy the hydrogen feast, you bastards!" Xiao Yu thought viciously.

Over three months, Xiao Yu launched about 300 hydrogen bombs. Even if only thirty of them detonated, they would cause catastrophic radiation damage to the alien planet.

Xiao Yu even estimated that if bombs of the same yield detonated on Earth, the radiation would cause such severe cancer and birth defects that the human population would dwindle from 7 billion to less than 1 billion within a century.

This would almost mean the extinction of humanity. Of course, Xiao Yu didn't know the biological structure or radiation resistance of these aliens, but judging from their previous panicked response to the hydrogen bombs, they were also deeply fearful of them.

"Explode, explode." As the anticipated explosion time approached, Xiao Yu's eyes gleamed as he stared intently in the direction of the alien planet.

In the distance, a faint flash of light suddenly appeared, quickly fading. The brightness of the flash was even less than some distant, dim stars. But considering that the planet was over 30 million kilometers away and the light was still visible to Xiao Yu, its intensity was unimaginable.

Xiao Yu's heart raced with excitement, and he immediately began calculations.

The results confirmed that the flash was indeed from Xiao Yu's first hydrogen bomb!

In the glow of the explosion, Xiao Yu also observed the faint light reflected by the planet.

This confirmed that everything was as Xiao Yu had predicted! Their planet was indeed at that location.