April 2027, Rocket City, Luminous Nation
Professor Braun's home was located in a community on a semi-hillside in the southeastern suburbs of Rocket City.
Daphne Braun curled up on the living room sofa, her legs wrapped in a thin blanket, looking like a wounded kitten. Professor Braun and David sat on two single sofas by the window, facing each other.
David said to Daphne, "Daphne, you are absolutely safe now, there are agents from the Investigation Bureau guarding outside 24 hours on rotation. It's over, I hope you can relax."
"Yes, Daphne, Daddy is here, it won't happen again," Professor Braun said affectionately, continuing, "You've already given your statement this morning, I know it's annoying, but David and I still hope you can recall the details once more, it could be very important, child."
"Dad, I'm fine, Uncle David, thank you for bringing me back from Strong Nation so quickly." Daphne nodded towards David with a smile, then said, "Actually, I've already detailed everything during the statement this morning. I was knocked out while jogging, woke up in a small room made from a shipping container, there was a metronome, a mattress, and a talking speaker, with background recordings of metronomes at 20 and 40 BPM alternating, and then a cell phone fell out."
"They had me deliver a message, 'little girl,' and said they'd pay me nearly $50,000. That's all, no more details."
David, thoughtful, stood up, gesturing for Professor Braun to follow him out. Before leaving, he said to Daphne, "Take a rest for now, Daphne. In a while, the bureau's psychologist, Kristen, will come to talk with you. It's standard procedure, hope you don't find it bothersome.
Trust me, psychological counseling will be beneficial for you."
Professor Braun led David out of the living room, closing the door behind them, walking through the porch into the study on the other side.
David turned to close the study door, saying, "We've checked Daphne's account, one of them had a deposit made after she was kidnapped."
"How much? Can we trace the depositor's account?" Professor Braun asked, surprised.
"The depositor's account is real, belonging to a bank branch in Uplift Nation, but the account owner was unaware, the kidnapper had stolen this account, it'll be hard to trace back to the source," David said.
"What a strange thing! Kidnapping a hostage, not asking for a ransom but instead giving money, what does this mean?" the professor wondered aloud.
"The kidnapper did say, passing a message, 'little girl,'" David explained, then added, "What's even more puzzling, the kidnapper didn't deposit money, but gold certificates! 31.9 ounces of gold certificates. Since Daphne only had a dollar account, not a gold account, as per banking practice, the receiving bank automatically converted it into dollars at the closing price of gold on the Neith Commodities Exchange that day."
"Professor Braun, do you know the recent price of gold?" David asked.
"I'm an astronomer, not a gold trader, though I do watch financial news. I don't know the exact price of gold, around $1900 per ounce, roughly?"
"Not bad, my astronomer! Indeed, the price of gold has been fluctuating around $1900 per ounce recently."
David, teasing, made a mysterious expression, saying, "What's strange is, on the day of the deposit, a group of mysterious sellers, in the last hour before closing, dumped a large amount of gold, actually pulling the closing price of gold down to about $1557 per ounce!
At this price, the bank converted 31.9 ounces of gold into $49669 and deposited it into Daphne's account."
"$49669?" Professor Braun sprung up from his chair, his mouth agape, staring intently at David.
David, somewhat bewildered, hurriedly asked, "What's special about $49669?"
"What's the international trading code for gold?" Professor Braun asked out of the blue.
"AU, gold's trading code is AU," David answered.
"Do you know what AU means in astronomy?" Professor Braun asked.
"Of course, Astronomical Unit, the distance from the Earth to the Sun, defined as 149,597,870 kilometers, is 1 AU," David replied.
"To be exact, 1 AU is 149,597,870 kilometers," Professor Braun added, then asked, "Have you heard of the Hyper-View Probe?"
"I've only been in your office at the Luminous Nation Space Agency for a few years, but I know in 2006, your team launched the Hyper-View Probe, which arrived and successfully took pictures of Pluto in July 2015," David said.
"Do you know how far from Earth the Hyper-View Probe was when it flew by Pluto?" Professor Braun asked.
David, a professional agent with strong analytical skills, seemed to understand something, tentatively asking, "31.9 AU?"
Professor Braun nodded deeply, continuing, "I thought I was overthinking, but the number 49669 clearly tells me, this is no coincidence."
David looked puzzled again, asking, "What does 49669 mean?"
"David, if I remember correctly, you're informed about the T project, you've signed a confidentiality agreement, right? Your security clearance is level two, isn't it?" Professor Braun said.
"Yes, I signed the confidentiality agreement in front of you and Mr. E when I was transferred here, my security clearance is level two."
Professor Braun pondered for a moment, then said, "Given your security clearance, what I can tell you is, besides taking photos, the Hyper-View Probe conducted a very important scientific experiment when it reached Pluto. I can't tell you the content of the experiment, but your clearance level allows you to know the significance of the experiment's special timing," Professor Braun continued, "When we launched the Hyper-View Probe in 2006, we had already decided it must fly by Pluto on July 14, 2015, because that specific date was the best timing for that experiment. Nine and a half years of flight, hibernation, re-ignition, multiple attitude adjustments, we finally made the spacecraft fly by Pluto exactly on July 14."
"July 14, 2015, what's special about that day? F nation's national day, what does that have to do with it? Oh right, the Jade Khanate nuclear agreement signing day? That's not related either!" David racked his brain, clueless.
"Have you heard of the constellation Leo? The α star of Leo is called Regulus, it's one of the brightest 20 stars in the sky, and also the one closest to the ecliptic plane among these 20 stars, which we call a co-planar star."
The professor, as if back on the lecture podium at Golden State Institute of Technology, continued, "Jupiter orbits the Sun with a period of 11.86 years, and there's always a day in each cycle when it aligns with the Sun and Regulus, astronomically called Jupiter in conjunction with Regulus regarding the Sun. Simply put, it's when the Sun, Jupiter, and Regulus are in a straight line."
"July 14, 2015, was this astronomical event, and also the carefully chosen day for the Hyper-View Probe to reach Pluto for the experiment."
David looked astonished, it was like hearing a myth! He asked, "What does this have to do with the number 49669?"
Professor Braun calmly and meaningfully replied, "The European Space Agency assigned codes to hundreds of thousands of stars, and Regulus's code is HIP 49669."
David took a deep breath, saying, "My goodness! The kidnapper wants to tell us that they know the significance of the Hyper-View Probe's special date of arrival at Pluto?"
Professor Braun shook his head helplessly.
A "ding" sound came, David looked at his phone notification, which read: "Found it, the behind-the-scenes seller dumping the gold was the Central Bank of the Jade Khanate."
David showed Professor Braun his phone while hurriedly saying, "The one sending us the message was the government of the Jade Khanate."