It all started with a simple question.
“How high can you fly?” asked Twilight Sparkle, interrupting her friend’s rambling narrative about her plans to improve the aerial acrobatics display she’d just spent the last two hours practicing.
“What?” Rainbow Dash replied, looking at Twilight as if she was crazy. “Were you even listening?”
“I figured you were mostly talking to yourself at this point,” the unicorn replied, rolling her eyes as she got to her feet. One of her legs got caught in the blanket she’d wrapped herself in against the chill autumn air, but she managed to untangle it with her magic without falling down or looking too foolish. “But I was thinking about your flying, and you didn’t seem to have much trouble flying straight up when you needed to. What would happen if you just kept going?”
“I’d get bored,” Rainbow Dash said, in a tone of voice that already sounded bored just thinking about it. “Do you think I haven’t tried it? Every pegasus tries it at least once. Except for Fluttershy, of course.”
“Yes, but how high did you get before you had to stop?” Twilight asked. “I’ve heard that the air gets thinner and colder, the higher you go…”
“Yeah yeah,” Rainbow said, waving that off with a wing, “Pegasi don’t really care about that. I mean, we can tell that it’s cold and that the air is thin but it doesn’t really bother us. But there’s nothing up there, Twilight. You get a few miles up and even the wispy cirrus clouds peter out, and then it’s just empty air forever. Unless you’re asking if I could fly to the moon or something.” She stifled a giggle at the look on Twilight’s face. “You are! You think I could fly to the moon! BWA HA HA HA!”
Twilight looked distinctly unamused.
“You can’t fly to the moon, Twilight,” Rainbow Dash said. “It’s basically, like, a million billion miles away. I’ve flown up until all of Equestria was like a big blue and green ball beneath me, and the moon was just as far away as ever.”
“So you don’t know if you could fly there, because it’s far enough away that you got bored,” Twilight said, folding up the blanket she’d been sitting on and stuffing it into one of her saddlebags.
“You try flying through an endless empty void sometime and tell me how far you get before you turn back,” the pegasus replied, hovering over Twilight’s head and poking her on the horn. “For a pony that likes boring stuff you get bored faster than anypony. You didn’t last ten seconds when you thought you had to stand there and do nothing all week.”
“I bet you’d get bored before I would,” Twilight said, her horn glowing as she lifted and folded the blanket lying across her back and put it in the other bag, shivering a little – it wasn’t a long run back to Ponyville, and the exercise would keep her warm. She trotted around Rainbow Dash, then turned back to add, with a smug little smile, “I’d bring a book.”
“You wouldn’t get bored because you’d freeze to death,” Rainbow pointed out.
“Oh,” Twilight said, sheepishly, “Right.”
===
Later, at Pinkie’s ‘Last Night of Fall’ party, Rainbow Dash giggled to Pinkie Pie by the snack table as she recounted the conversation. “…and then it turns out she thought I could fly to the moon!”
“Well, how high can you fly, Dashie?” Pinkie asked, dribbling a bit of hot sauce into her punch. She’d learned better than to spike the punchbowl.
“I can fly as high as I want,” Rainbow Dash said.
“So, would you like to fly to the moon?” Pinkie Pie said. “I know I would! I mean, I’ve heard the moon is made out of glowing magic moon cheese that Luna had to eat for a thousand years, and covered with all her notes on how to conquer Equestria, and even if I didn’t find that I could look down at Equestria and wave to everypony at once! Not to mention all the parties I could throw for the poor moon ponies. I mean, do they even have parties on the moon?”
“I guess it would be kind of cool,” Rainbow Dash said. “I mean, can you imagine it? I’d be the first pony to go to the moon under her own power."
“So then you can’t fly as high as you want,” Pinkie Pie said, shaking her head. “So sad!”
“Nnng!”
“I wouldn’t worry about it, Rainbow,” Fluttershy said quietly, as she gingerly set a cucumber sandwich on her plate. “The ground’s much nicer anyway.”
“That’s it!” Rainbow Dash said, loud enough to draw every eye in the room towards her. She hovered up off the ground, and pointed a hoof at the pink pony who’d just joined Twilight and the others near the fireplace. “Pinkie Pie, I’m taking you to the moon!”