46. The Descendant of Arsen

— Report from Survey Vessel J01-002 to the Imperial Survey Bureau

— Jump-out successful

— Level 3 intelligent life detected in target star system, third planet

— Proceeding with detailed investigation in accordance with Level 3 Intelligent Life Contact Protocol

— Launching Survey Probes One through Four toward the third planet

……

"Is this the small spacecraft that suddenly appeared in the Sol system, conducting FTL communications near Uranus’s orbit?"

Currently, Ain—acting representative of Agirakana and acting ambassador to Japan—is confirming via the operation desk screen in the Agirakana Representative's Office on the eighth floor of the Agirakana Embassy to Major General Bruus Tarymte, captain of the H3-class assault landing vessel AA-0001—Blazer.

The shape of the spacecraft displayed on the screen was a spindle-shaped main body, adorned with numerous protrusions and appendages—some spherical, others rod-like—attached in a highly complex configuration, with what appeared to be thruster nozzles scattered at irregular intervals. To Ain, who was accustomed to Agirakana vessels, it looked excessively wasteful and distinctly outdated. What struck her most was the design’s utter disregard for potential impact—she had never seen anything quite so… unconsidered.

"The starship's drone—captured by the orbital vessel SII-001 stationed at Jupiter. They say they handled it with care, since detonation would be inconvenient. During the capture operation, four drones were launched, apparently toward Earth, but all were secured. Caution was exercised, but it appears this vessel never had a self-destruct mechanism to begin with. Perhaps a product of a civilization not quite used to such... theatrical measures. Analysis of the drones’ interiors, conducted within the blazer chamber, revealed they were all designed for planetary surveying. The main body’s transmitted signals are still under analysis, but they likely reported either the discovery of a habitable planet within the solar system, or perhaps a sufficiently advanced intelligent species."

"Have you managed to determine where the starship was sending its hyperspace transmission?"

"After examining the hyperspace communication device aboard the starship, the most likely system was identified as one approximately 300 light-years from this solar system, centered on a G-type star. For now, the system has been designated DT-01. Multiple planets have been confirmed within DT-01, including at least one Earth-like world."

"It’s surprising, admittedly, that a civilization capable of constructing starships—undetected by Agirakana—exists at such a relatively close distance. But what of the technical characteristics of the captured vessel?"

It’s confirmed the vessel possesses a jump drive at the same level as Agirakana’s—basically, one that propels it at a thousand times the speed of light. Its communication system reaches a radius of approximately two thousand light-years. Given that no ultra-high-density materials were found aboard, it seems unlikely they possess the hull technology we do. Moreover, no gravitic thrusters were used in the propulsion system. The complete reliance on conventional, propellant-based thruster technology further corroborates the absence of hull technology.

The propulsion system, too, carried only a reactor capable of one-stage fusion from hydrogen—no antimatter, no annihilation reactors of any kind. Altogether, it was unmistakably archaic and ponderous. Whether the weaponry was advanced or not remained unclear, as we had not seen any warships firsthand, but the technology seemed unlikely to be sophisticated. All systems except the jump drive bore a striking resemblance to the very earliest iterations of Arsen technology.

Until Agirakana returns from its expedition, we will lack a combat vessel for space warfare. Yet, even if a fleet composed of warships derived from the captured vessel’s technology were to appear, our strike wing alone should suffice to handle it.

Understood. The threat level appears low, but please reinforce patrols in the outer solar system. In addition, could you expedite the production of antimatter for the annihilative reactor and annihilative munitions on the Blazer, just to be safe.

As you said, if the technological framework closely resembles that of Arsen, there's a possibility they're descendants of the lost Arsen—somewhat inconvenient, to be honest.

Noted. I'll leave the complicated business of Arsen's descendants to you. By the way, it might be wise to assign escorts to the currently operating solar cruise vessels.

Yes, I'll contact the cruise ships directly. If possible, please have the escorts dispatched as soon as feasible.

It'll be good training for the attack pilots—no issue there. The farm station in Earth's geosynchronous orbit can defend itself, and it's close enough to the Blazer, so that shouldn't be a problem either.

Two months after destroying the neutron star that spawned Zeno, the Agirakana were expected to appear in the Sol system only twelve years hence. Yet Ain remained uncertain about what judgment to make—if, indeed, the primary core constituting the Agirakana’s core had emerged as a new descendant of Arsen, the implications were unclear, and that uncertainty unsettled her.

Further investigation of the captured unmanned micro-spacecraft aboard the Blazer revealed it bore a striking resemblance to an unmanned probe used over a millennium before Arsen’s extinction. Whether this was a true descendant of Arsen or merely a technological echo remained unconfirmed.

The manufacturer’s form, inferred from the vessel’s shape and its ornate appendages, was humanoid—slightly belligerent in posture. Given the absence of a self-destruct mechanism, it was speculated that the civilization had not experienced prolonged conflict with peers of comparable advancement. Later analysis of signals emitted by the captured unmanned vessel confirmed, as Captain Blazer’s Major Brue had conjectured, that they had discovered an advanced sentient lifeform.

The heavily armored, high-speed scout vessel was ideally suited for reconnaissance and survey missions, so it would have been convenient to dispatch it to the star system where the unmanned vessel had presumably transmitted signals. However, Ain currently lacked the authority to recall any scout vessels engaged in active operations. The only immediate option, therefore, was to deploy the scout drones already on hand. Consequently, the two jump-drive-equipped scout drones—previously loaded onto the Blazer by Agirakana before the jump—were sent toward the target planet. They were expected to transmit as much data as possible back to the Blazer, which was waiting in orbit around Sol, before being detected by the enemy's sensor net and detonating in a final, futile burst of information.

Six days later, the scout ship—conveniently designated System DT-01—jumped out into the system, immediately transitioning into stealth mode as it approached the third and second planets, emitting various signals while beginning data collection. Multiple hyperlane gates were confirmed within the system, and it became apparent that numerous spacecraft were currently traversing it. Yet the opposition seemed utterly incapable of detecting a scout ship of such minimal mass; the two probes ultimately went unnoticed, successfully infiltrating into satellite orbit above the third planet. They continued relaying data—video, language, cultural patterns, scientific level—to Blazer, and onward to Ain at the Agirakana Embassy in Tokyo.

The video feed from the two probes sent this time showed multiple orbital elevators constructed in geostationary orbit around the third planet of the DT01 system, with what appeared to be warships gathering near the docking pier of one of the elevators, forming a small fleet.

The final composition of the assembled vessels consisted of four smaller ships equivalent to Agirakana destroyers, plus twelve additional smaller craft, and two medium-sized vessels resembling transports. The eighteen-ship fleet then drifted away from the system’s outer edge, their thrusters glowing a bright blue-white.

In the DT01 system, humanoid intelligent life forms resembling the Arsenians inhabited the third and second planets in quantities measured in the billions, having formed a interstellar state known as the Great Arsen Empire. Artificial structures were also present within the system, and starships appeared to be actively traversing its interior.

From signals intercepted by the probe deployed from the Blazer, it became apparent that the Great Arsen Empire consisted of twelve inhabited star systems and multiple developing colonies, with a population exceeding thirty billion. The systems seemed to be linked by hyperlane gates. Analysis of the data suggested that, aside from jump drive technology, the Arsenians’ scientific capabilities were comparable to those of Arsen roughly one thousand to fifteen hundred years before Arsen’s collapse—how such a sudden leap in technological advancement, particularly the emergence of the jump drive, had occurred within the Great Arsen Empire remained unclear.

The Great Arsen Empire refers to the G-type star at the center of the DT01 system as Hamilapiratra, and its capital planet—the third planet—as Azeen. A small fleet departing from near the primary world Azeen and heading toward the outer edges of the system appears to have performed a hyperspace jump there. If that fleet is en route to the Sol system, it could emerge into that system in approximately three months.

Ain considered modifying the remaining probe equipped with a jump drive to infiltrate an operative extracted from the ground assault unit’s special forces into the capital planet of the Great Alze Empire, Azeeen. However, with Agirakana absent, establishing a backup system proved difficult. Moreover, by the time their own operative arrived at Azeeen, the Great Alze Empire’s advance force would likely already be arriving at the Sol system. Thus, he decided to wait and assess the situation after responding to the Great Alze Empire’s advance force.

[Supplementary Explanation]

Farm Stations

Multiple agricultural and fisheries-focused space stations, known as Farm Stations, have been constructed at the Lagrange points L1 and L2 between Earth and the Sun, as well as along Earth’s geostationary orbit. They primarily cultivate feed crops, plankton for aquaculture feed, and small fish.

Hull and gravitic thrusters

Ships with hulls, due to their extreme mass, become impractical to accelerate using any propulsion system other than gravitic thrusters—beyond a certain point, conventional propellants simply won’t cut it.