Every Wednesday at noon, an old man named Tenjō shows up at the observatory cafeteria. He’s not staff. Rumor has it he’s a retired resident from a nearby apartment complex, though nobody has ever bothered to confirm it. He always takes the same window seat, orders the same grilled fish set, and starts, without fail, with the miso soup.
That day I was just there by chance. Comet season had packed the place, and the only open seat was across from him.
He’d drunk about half his miso soup when he spoke, eyes still down.
“The blue one is a lie, you know.”
“Sorry?”
“The comet. The blue tail. It’s a lie.”
From the back of the cafeteria I heard one of the lunch ladies murmur, “Oh, Tenjō-san’s off again,” followed by a small laugh. Apparently this was a regular bit.
I set down my chopsticks. As someone who’d covered ion tail physics in undergrad, I felt the instinctive twitch of correction. CO⁺ ions excited by solar UV, re-emitting as blue fluorescence. The dust tail reflects sunlight white. Different shapes, different lengths, different orientations. Hundreds of observation photos on record. No room anywhere for the word “lie.”
“When you say lie, you mean—”
“Not the physics. Nothing to do with the physics.”
He put down his spoon with a slightly weary air.
“My lie. Not the blue tail’s lie — my lie. I told a lie about the blue tail. That’s the story.”
“Ah.”
“Long ago, on my first date with my wife, we went to see a comet. Took a bus up to a parking lot halfway up a mountain — that kind of thing was fashionable back then.”
The conversation had jumped decades in a single sentence. I kept quiet and waited.
“Honestly? Until that night, I had no real sense of the difference between a comet and a meteor shower.”
“Sorry?”
“I knew they were different things in theory. But in practice I had them mixed up. I went expecting something like ‘a night when lots of shooting stars fall.’ It never crossed my mind there’d be a star hanging in the sky dragging a tail behind it.”
He turned his teacup slowly in his hands, looking mildly embarrassed.
“Then my wife pointed up and said, ‘Can you see the blue tail? It’s so beautiful.’”
“Right.”
“Honestly, I couldn’t even tell which one was the comet. There were a few blurry glowing things in the sky and I had no idea which one she was talking about.”
”…I see.”
“But I said, ‘Yeah, it’s so blue and beautiful.’ Because I figured if I said ‘which one?’ the whole moment would die.”
I split the tofu in my miso soup with my chopsticks.
“And then we got married.”
“Wait—”
“Well, a lot of things happened after that. But that night was the starting point. The lie about the blue tail.”
He kept talking while neatly picking the bones off his grilled fish.
“Ever since, whenever a comet comes up, I feel a little guilty. The world goes on about the blue tail, the blue tail. But to me, the blue tail is that dodge from that night. Pretending I could see something I couldn’t see at all. That lie.”
“Right. I think I understand.”
“So — the blue one is a lie. For me, anyway.”
With that, he grabbed his receipt and stood up. A small bow: “Enjoy your meal.” And he was gone.
I stared at what was left of my miso soup. What a load of nonsense, I thought, somewhere inside my mouth.
Not that I don’t get it, in the abstract. A fib that bent the course of a life. The origin point of fifty-odd years with the same person. Sure. Fine. But broadcasting that precious little private confession under the sweeping claim that “the blue tail is a lie” — every single week — is not something the rest of us can do much with. CO⁺ is blameless. It’s out there fluorescing honestly, and one old man’s social instinct is getting it branded a liar.
That evening I took my shift in the observation dome. Tonight was C/2026 B, stacking long exposures every three hours. I was tired. The photometric calibration from yesterday wasn’t done yet. My laptop had the uncalibrated histogram still open on-screen.
The processed image came up on the monitor — layers of exposure building into something. The blue tail stretched thin and true to the upper right, just like the textbook. The dust tail curved softly in a pale white arc.
Beautiful? Honestly, I wasn’t sure. What I’d been looking at for the past hour wasn’t the shape of the tails but the background light gradients and the S/N readout jittering every time a wisp of cloud drifted through.
My phone buzzed. Aoi.
“Hey, have you seen tonight’s comet yet? It’s on TV — they’re saying the blue and white tails are incredible.”
I was almost certainly the human being closest to this comet in the entire world right now. Sitting right below the telescope, counting photons one by one. Aoi doesn’t know much about astronomy. She always asks: Is it beautiful out there at the observatory at night? I always give her some vague answer.
I moved my thumb and typed.
“Yeah, the blue was absolutely gorgeous. I’ll send you a photo later.”
After I hit send, I stared at my own thumb.
I had told the exact same lie as Tenjō-san.