On the third day after the discovery of the strange black ring.
Black Lady One reentered Earth's atmosphere and slowly landed at the Xia Country National Aerospace Research Institute.
The rock and black-ring samples excavated on the Moon were immediately sent to the institute's laboratory.
Lü Yongchang gazed at the black substance on the laboratory bench before him, a trace of wonder flashing in his eyes.
Under the lights, the black substance had a faint reflective sheen.
"I have to say, this stuff is actually pretty," Lü Yongchang said quietly.
Cao Liangcai leaned over, glanced at the black substance on the bench, and nodded slightly. "It really is pretty, but..."
"They used a Hall Thruster too, yet ours can't seem to produce this effect, can it?"
At those words, a hint of helplessness appeared in Lü Yongchang's eyes.
Of course it couldn't.
If theirs could achieve the same effect, Black Lady One could probably fly out of the Solar System.
"Cao, help me determine when this stuff formed."
Cao Liangcai froze for a moment.
"When it formed? Why are you studying that?"
"Shouldn't our first priority be analyzing the composition of this black substance?"
Lü Yongchang's penetrating gaze remained fixed on the glasslike material before him. "I want to build a model and work backward to figure out where that spacecraft went!"
"The results are in."
There was a hint of horror in Cao Liangcai's eyes. "You might not believe this, but this stuff actually formed five years ago!"
"It's hard to pin down an exact date. We only have an approximate timeframe, probably around December 2025."
At that crucial date, Lü Yongchang's heart sank.
Five years ago.
That was exactly when the Voyager probes had left the Solar System.
*Surely we couldn't be that unlucky... Had the two