July 10, 3900.
A report was brought to Jin.
It came from the Sirius, Procyon, and Betelgeuse.
These spaceships had been dispatched on an assignment to measure whether the region of high-concentration free ether centered on Star Celane was expanding.
The mission was scheduled to last about a year, meaning this was an interim report.
"My Lord, I will begin with the conclusion. The high-concentration space is expanding."
Laojun delivered the update.
"I see..."
The ships had been sent out in March of that year.
Confirming expansion after only four months of observation meant the rate of growth was remarkably swift.
"Around when will it begin affecting Hehl or Ars?"
That was Jin's primary concern.
"Yes, My Lord. Taking into account that the volume of the space increases as it expands, it will reach them in approximately 12,500 years."
"That far off?"
It was often said that the sheer vastness of space was difficult for ground-dwelling humans to grasp, and this seemed to be a prime example.
On a cosmic scale, ten thousand years was hardly a long span. For mortal beings, however, it was an eternity.
"We just have to find a way to consume free ether by then."
In fact, there was no telling if living creatures would even remain on Planet Ars that far into the future.
"Even so, please continue the measurements for the scheduled duration."
One never knew what might happen in this world.
There was no guarantee that the expansion rate wouldn't suddenly accelerate.
"Besides, we still don't even know why free ether is radiating from Star Celane in the first place."
"Understood. Then I shall have the three ships continue their measurement duties for the full planned year."
"Please do. In the meantime, I'll build dedicated sondes to establish a system for monitoring the boundary."
"Understood."
As an aside, the reason Jin occasionally used technical terms of German origin was that the books forming the bedrock of his knowledge were slightly dated.
Back in the Showa era—specifically the late 1950s and 60s—certain technical terms that have since been replaced by English were still spoken in German, and science magazines from that period were kept in his orphanage facility.
Incidentally, "sonde" was a German term, equivalent to "probe" in English.
Weather observatories, the Self-Defense Forces, and other research institutions used "radiosondes"—instruments attached to balloons to measure high-altitude atmospheric conditions—which was why Jin referred to this measuring device as a sonde.
For the same reason, Jin referred to climbing ropes as seil, or pronounced -saurus as -zaurus when naming dinosaurs. (In English, the "s" is unvoiced, making it -saurus.)
Be that as it may.
"A microsatellite spaceship equipped with a magi-communicator, a barrier, and simple self-defense measures... I suppose that's what it comes down to?"
"Indeed. A self-repair function would also be desirable."
"Yeah."
With a diameter of one meter, its force generator gave it an acceleration capability of 10G.
For defense, it was equipped with a standard barrier, along with the Aegis to ward off meteorites.
For emergencies, its transporter allowed for a ten-kilometer teleportation.
Jin would build six of these: four stationed along the planetary orbital plane, and two positioned toward the upper and lower magical poles. In other words, they would form the vertices of an octahedron inscribed within the spherical high-concentration space.
They would exchange information with one another via communication, ensuring they could cover for each other if any malfunctions occurred.
"This should do it."
"Yes, My Lord."
Jin spent three days completing the six units.
"All done."
"Yes, Father."
Jin named these measurement microsatellite spaceships "Sondes 1 through 6."
"Let's have the Sirius, Procyon, and Betelgeuse act as backups in case anything goes wrong."
"I believe that is a sound plan."
With this, Jin felt relieved, knowing they had taken all the precautions they currently could against the high-concentration free ether space.
"I need to start thinking about Planet Hehl soon, too... But before that."
Jin felt he ought to meet with Elder No. 700672.
"Reiko, we're going to Hehl."
"Yes, Father."
Although he could have contacted him via manacam, Jin preferred to speak with the Elder face-to-face.
"...Laojun, the Elder is on Hehl, right?"
"Yes, My Lord."
Just as he was about to set off, Jin checked at the very last second. It was fine since the Elder happened to be on Hehl, but had he been at the stronghold in the northern Nord Federation, the trip would have been a waste of effort.
"Good, that settles it."
With that confirmed, Jin teleported over to Planet Hehl.
"Oh, Jin-dono, welcome."
On Hehl, Elder No. 700672 greeted him, appearing entirely unchanged.
Seeing his demeanor, Jin instinctively sensed that he had not fallen into Master Loss Syndrome. Relieved, he breathed an inward sigh of comfort.
Most likely, Marikka... or rather, Marikka's homunculus, was somewhere in this world—somewhere other than Planet Ars, Jin presumed.
A person who was supposed to be dead would only stir up confusion if seen.
Living in a place where nobody knew her was probably for the best.
Setting the matter aside, Jin explained the purpose of his visit.
"Hm, checking on the development status of Hehl? In short, it is proceeding smoothly."
What they prioritized above all else at present was restoring the natural environment.
Specifically, the regeneration of vegetation.
Now that the oceans were being replenished, precipitation was on the rise as well.
For now, rainfall was limited to coastal regions, but it would eventually increase dramatically inland.
If that happened, what would become of mountains with barren slopes? Jin knew the catastrophic consequences all too well from modern Japan.
That was why they were pressing ahead with reforestation.
However, planting trees at random was not the answer.
Vegetation ill-suited to the climate would quickly wither and die.
"We are consulting historical records and trying to match the original ecosystem as closely as possible, but..."
Using records in Elder No. 700672's possession, documents left behind on Onogoro Island, and materials recovered from other ruins, they were working to recreate the flora of bygone days.
"The dates on the surviving records are unclear, which makes it rather difficult."
Apparently, the vegetation in some regions varied depending on the era.
"In such areas, we have decided to adhere to the older records."
"So it's not quite straightforward, is it?"
"Indeed. However, the work of returning this world to how it was when the Masters walked here is profoundly rewarding."
Constructive, creative labor is a joy, the Elder said with a chuckle.
"I'm glad to see you enjoying it."
Jin smiled along with him.
Even so, he felt a faint pang of disappointment that Elder No. 700672 said nothing about Marikka.
I suppose it's not something he can speak of so easily, Jin thought, taking solace in the assumption.