unusual signal

Since the dawn of time, when primitive humans first gazed at the stars, mankind's exploration of the mysterious cosmos has never ceased.

Now, after eons of development, Xiao Yu has taken a monumental step forward.

Humanity has finally traversed a distance of one full light-year.

Yet, Xiao Yu is the last of his kind, the sole human left in the universe.

Here lies the Oort Cloud, a vast expanse one light-year from the Sun, about 9.5 trillion kilometers away. From here, the Sun appears dimmer than Sirius as seen from Earth. The Sun has truly become just one among countless stars.

In the distance, a dark meteoroid, roughly ten cubic meters in size, flashes by, speeding toward the Sun.

Xiao Yu smiled wryly. His observation confirmed that the gravitational pull of his fleet had altered the meteoroid's trajectory. According to calculations, in several thousand years, it will enter the inner solar system, blazing a glorious comet tail before being vaporized by the Sun.

Here, in the Oort Cloud, billions of meteoroids are scattered throughout the vast darkness. Their combined mass is estimated to be ten times that of Earth. They are remnants from the Sun's formation, expelled from the inner solar system billions of years ago due to gravitational skirmishes with gas giants like Jupiter. Only a few of these meteoroids will ever encounter the Sun again.

The distance from the Sun is so great that even other stars might exert influence on these objects. It is predicted that in several million years, a star known as Gliese 710 will pass close by, capturing some Oort Cloud bodies while pushing others toward the inner solar system.

Xiao Yu maneuvered his village-class spaceship deftly toward a meteoroid roughly the size of a few dozen cubic meters, capturing it within the ship. These meteoroids contain traces of the early solar system, crucial for Xiao Yu's research on stellar evolution.

Aside from the two meteoroids Xiao Yu observed, the Oort Cloud remains as desolate as any other region. Without pause, Xiao Yu continued his high-speed journey.

The Oort Cloud marks the outermost boundary of a star's domain. Beyond this, no celestial body is under the Sun's gravitational influence. Except for a faint starlight, the Sun has no power here.

Perhaps, in five billion years, when the Sun dies, its planetary nebula may extend to this place.

Countless moments slipped by as Xiao Yu left the Oort Cloud, over two thousand years ago.

After sixteen hundred years, all of Xiao Yu's spare parts were exhausted. Over the next four centuries, fifty village-class ships were abandoned. Their parts were salvaged and installed on other ships, replacing damaged components. These fifty village-class ships, now empty shells devoid of propulsion, were left to drift aimlessly through the infinite cosmos, doomed to wander forever.

Along with these fifty village-class ships, two township-class ships were also abandoned. Although the three county-class ships had undergone significant repairs, they were still functional and capable of continuing the journey.

The voyage was now forty percent complete, a distance of four light-years. If Xiao Yu's destination were Alpha Centauri, he would have already arrived.

Alpha Centauri, commonly known as Proxima Centauri, is a trinary star system, chaotic with three stars orbiting one another. Observations suggest that no stable planets exist there, so despite its proximity, Xiao Yu did not choose it.

Over these two thousand years, Xiao Yu passed through at least four large gas clouds. Each passage slowed his speed, requiring him to accelerate and correct his course.

Every acceleration and course correction consumed vast amounts of fuel. However, thanks to Xiao Yu's extensive reserves at the start, the fusion fuel supply remains optimistic, sufficient to sustain Xiao Yu's journey to the Tianyuan-4 star system.

The largest of these gas clouds stretched one light-year in length and several light-days in width, taking Xiao Yu over twenty years to traverse.

In the universe, such large gas clouds are relatively common. Even the solar system was born from one such cloud. Billions of years ago, disturbed by a nearby supernova, this cloud began to collapse inward. Eventually, the density and temperature at the cloud's center triggered nuclear fusion, giving birth to the primordial Sun.

The powerful stellar winds of the young Sun dispersed the surrounding dust, which gradually coalesced into planets. After billions of years of evolution, these planets stabilized into their current forms.

If a celestial body were to exert influence on this gas cloud now, it might also give rise to a star in the distant future.

Unfortunately, Xiao Yu lacks the means to create a star, though he would relish the challenge.

The gas cloud reduced Xiao Yu's speed from 563 kilometers per second to 506 kilometers per second and caused a course deviation of one-thousandth of a degree.

Interstellar navigation demands absolute precision. The required accuracy is greater than hitting a mosquito on the Moon from Earth. Over vast distances, a tiny initial error would be magnified a thousandfold. If left unchecked, this deviation would cause Xiao Yu to miss his destination by hundreds of billions of kilometers.

Thankfully, Xiao Yu has a pulsar navigation system. Using signals from six pulsars, he corrected his course and continued his journey toward Tianyuan-4.

Here, five light-years from the Sun and five and a half light-years from Tianyuan-4, the voyage is nearly halfway complete. It has been three thousand seven hundred years since Xiao Yu departed from Saturn.

The number of lost village-class ships has increased to one hundred and thirty-five, while eight township-class ships have been lost. However, the three county-class ships remain fully operational. The reason is simple: the county-class ships are the most valuable. Xiao Yu often salvages parts from village- and township-class ships to maintain the county-class ships. Sacrificing smaller ships has ensured the survival of the larger ones.

Xiao Yu's fleet is like a band of refugees, losing members to cold and hunger along the way, their bodies callously abandoned.

Although nuclear fusion is the most efficient energy source known, and the materials used to build the ships represent the pinnacle of Xiao Yu's material science, they are still vulnerable to the passage of time. Until Xiao Yu achieves new technological breakthroughs, such losses are inevitable.

At five light-years from the Sun, the Sun's brightness has diminished further, blending indistinguishably with other stars. Meanwhile, Tianyuan-4's brightness steadily increases. With fewer gas clouds obstructing the view, Tianyuan-4 now appears brighter than the Sun.

Over these nearly four thousand years, Xiao Yu's technology has advanced, but only on a technical level. For instance, Xiao Yu now possesses a new model for photon computer architecture, which, once perfected, could produce a new type of computer with several times the processing speed of current photon computers, while being smaller and more energy-efficient. Xiao Yu has also developed more efficient fusion applications and insights into the internal mechanisms of Wood Spirit-enhanced materials. Xiao Yu can now simulate the Wood Spirit enhancement process using a strong magnetic field, though the efficiency still lags behind the original.

Another significant breakthrough lies in laser technology. Laser technology has two primary applications: offensive, in the form of traditional laser guns and cannons, and defensive, as in the legendary shield technology. Xiao Yu has formulated a preliminary theory for energy shield technology, which involves using a strong magnetic field to constrain high-energy photons into a protective layer around the ship. However, practical testing will have to wait until sufficient materials are acquired from the Tianyuan-4 star system.

In contrast, fundamental physics has seen no groundbreaking developments. But Xiao Yu is not worried. He believes that once he reaches the Tianyuan-4 star system and builds a large particle collider around it, breakthroughs in fundamental physics will follow.

Xiao Yu has a tentative hypothesis: if the large particle collider at Tianyuan-4 succeeds in detecting the Higgs boson and thereby confirms the Higgs field, Xiao Yu might unlock a nearly infinite energy source, at which point all the obstacles to his journey will vanish into dust.

This underscores the brilliance of both relativity and quantum theory. Even with interstellar travel capabilities far beyond human technology, Xiao Yu is still fundamentally relying on the principles of relativity and quantum theory.

The endless voyage continues. Suddenly, the lead village-class ship detects an unusual fluctuation.

It's a brief, patterned radio wave. Xiao Yu can confirm that this wave was not emitted by his fleet.

This signal immediately commands all of Xiao Yu's attention. However, the signal was too brief for Xiao Yu to pinpoint its source. After some thought, Xiao Yu makes a decision.