Twilight Sparkle stared at Rainbow and Pinkie in disbelief. "You're going to what?"
It was the next morning, and the Element bearers had all gathered in the map room in Twilight's castle. With them were Spike, Starlight Glimmer, and Princess Luna.
Pinkie beamed. "Be the first ponies to pilot a rocket into space," she repeated patiently, "and land on the Moon, so Dash can be the first pony to walk on it."
"Uh, Pinkie..." Twilight said, "Princess Luna was up there for a thousand years. If any pony counts as being the first on the Moon, she does."
"Actually," Luna gently corrected, "I was imprisoned within the Moon, as part of its astral signature. Neither I nor the Moon were corporeal for that time. So in point of fact, I never set hoof on it."
"But Dash and I are gonna GO there, for realsies!" Pinkie enthused. "Princess Luna will make it a real place, so we can go!"
"But we need your help, Twi," Dash explained. "Princess Luna has agreed to power the overall trans-figure-whoozit spell..."
"Transfiguration," Twilight dryly corrected.
"Yeah, that. But to make the spell work, we need to dope out, uh... a whole lot of technical stuff..." She waved her forehooves vaguely, glancing hopefully at Princess Luna.
"Indeed," Luna said. "As I understand it, the whole point is for the journey to be as realistic as possible. So we shall need a detailed physical and technological basis for the reality we desire, in order to properly summon it. Given my... ahem... absence over the past millennia, we shall need the advice of a pony more deeply versed in modern science and its discoveries. And further, once the spell is invoked it cannot be altered, only cancelled, so it will be necessary to be as complete and thorough as possible in the spell's construction."
"And we immediately thought of you, Twi," Rainbow said proudly. "If any pony can science the hay out of this, it's you!"
"I'm flattered, Rainbow. Really." Twilight eyed her. "But if the point is to walk on the Moon, why can't Luna just teleport the two of you there? Once she's made it corporeal, that should be easy enough."
"Because it's not about getting there!" Rainbow pounded the table. "It's about going there... training hard for it, making the journey, facing the risks, proving we've got what it takes! Following the example of one of my greatest fillyhood heroes..."
"... a fantasy movie character."
"Twi!" Rainbow stared at her in frustrated disbelief.
"Relax, Rainbow. I'm not opposed to the idea." Twilight said. "If it means that much to you, I want to help. We all do. Right, everypony?"
There were willing nods around the table.
"It just seems, I don't know..." Twilight shrugged. "... a little excessive and roundabout, going to all this effort and trouble..."
"You know, Twilight..." Starlight said cagily, "the physics of this is actually pretty interesting." Picking up a quill in her magic, she sketched a quick diagram on a piece of scrap paper. "If we assume that we redefine Equus as a sphere, with the Moon another sphere orbiting around it, then gravity has to behave entirely differently. It won't be a rectilinear, pervasive field like we're used to... it has to operate as a polar field, drawing objects to a point, say at the center of the planet. And that would imply objects have some property, call it 'substance', that this force acts on..."
Twilight stared at the diagram, her eyes lighting up. "Hey, right! And given the polar nature of the field, it would act on this 'substance' in inverse proportion to the square of the distance. Which means air would tend to collect around the surface of the planet. Which would leave..." Twilight's jaw dropped, her eyes went wide. "... an airless vacuum! Just like in the movies!"
"And rocket engines..." Starlight said, "they might operate like larger versions of Trixie's fireworks... although we'd want to provide a means to control the rate of fuel flow, to make them manageable."
"And..." Twilight realized, "if a spacecraft was up high enough, and moving fast enough, it might be possible for it to fall right around the planet, and never actually hit it... and that means that to anyone on board, falling at the same rate as the ship, it would seem like there was no gravity on board at all... wait a second..."
Twilight grabbed a quill herself and began scribbling equations involving disturbing numbers of tensors and Cristhoofle symbols. In short order both she and Starlight were buried in calculations, muttering intensely to each other.
Applejack chuckled, watching them. "Ah think we've lost 'em for a bit. We should leave 'em to it, let 'em come up for air in their own time. Maybe we should work out some of the other details while we're waitin'... like who's doin' what?"
"Well, I call being Commander and Chief Pilot... obviously!" Rainbow looked smug. "And naturally I'm gonna want my favorite co-pilot along. (*) How about it, Spike? Ya up for the adventure of a lifetime?"
"Who me?" Spike perked up, smiling. "Sure, Rainbow!"
"Awww!" Pinkie looked crushed. "I wanted to be co-pilot!"
"You can be mission specialist," Rainbow told her. "That means you're in charge of running experiments and stuff."
Pinkie brightened up immediately. "Okay!"
Twilight looked up at the mention of experiments. "That's a great idea, Rainbow! I can plan out a schedule of experiments for Pinkie to run, both onboard and when you land on the Moon. After all, even if reality will go back to normal when this spell terminates, we should try to learn as much as we can about the reality we're constructing, for future reference. Like they say... more data is good data!"
"You got it, Twi!" Pinkie said. "And don't forget Gummy! He can be the ship's mascot!" She held the alligator up proudly.
"All righty, then," Applejack said. "Sounds like we got ourselves a crew. And we're gonna need space clothes for them to wear." She looked at Rarity. "Ah'll bet you can design some proper, stylish space duds for everyone, sugarcube."
"Already on it, A.J.!" Rarity had been busily sketching on a piece of parchment, and she held it up. "Voila!"
Rainbow eyed the result in disgust. "Rarity! We're going to the Moon, not down some runway! So lose the sequins and feathers. We're gonna need something practical, rugged, and air-tight. Look, I'll loan you some copies of the comic books. That'll give you an idea of what we're looking for."
"Comic books?" Rarity looked briefly discomfited, then she noticed Spike looking at her, and shrugged. "Oh! Er, well... if we must, we must."
"Umm..." Fluttershy said nervously, "is there anything I can do to help?"
Rainbow thought briefly. "Sure! You can be Capcom. That's the pony on the ground who's responsible for relaying messages to and from the crew, and making sure nopony forgets about us up there. It's usually a fellow equuinaut, but you're a fellow pegasus, and that's good enough for me."
"Oh! Sure, I'd be happy to do that!"
"All right," Applejack said. "And we're gonna need somepony on the ground runnin' the show. Kinda like the ringmaster at the circus. Ah figured that'd be Twilight, but Ah got a feelin' she might be tied up working the spell-castin' end of thangs."
"Well, why don't you do it, A.J.?" Rainbow said.
"Me? Shoot, Ah wouldn't be no use! You could fit what Ah know about space on a postage stamp."
"But you're good at keeping ponies organized," Fluttershy pointed out. "Getting them working together as a team. We'll have ponies managing all the complicated details, but we do need somepony like you keeping track of everyone, making sure we're not going in different directions."
"Wayall... if y'all think that'll work, Ah'm game to give it a try. Any other roles we should assign while we're at it?"
"One thing I would suggest," Luna said, "is our proposed crew has members of the pegasus and earth pony tribes... we should consider adding a unicorn crewmember as well, so that all three tribes are represented."
"No argument here," Rainbow said. "The Wonderbirds always had a spellcaster on the crew. But who's it going to be?"
"Cain't be Twi or Starlight," Applejack said. "We'll want them here, makin' sure nothin' goes wrong with the spellwork."
Starlight looked up from her calculations. "And Trixie's out of town, doing her magic show."
Rarity suddenly realized everyone was looking at her.
"Oh, uh... me? Ah... well, I'm really not sure about that. It sounds rather dangerous..."
"It'll be fine, Rarity!" Spike looked up at her. "We'll have Twi and Starlight designing the spell, Celestia and Luna running it, Rainbow and me co-piloting, and everpony down here pulling for us. It'll be an adventure!" He put out a claw to touch her hoof. "And it'd be really great if we could share it together... please?"
"Oh!" Rarity stared at him, and then smiled warmly. "Well... ahem, I suppose if I am going to be designing space clothing, it'd be only fair to be able to try it out myself. I tell you what, Spikey-wikey... I'll go along, but only if I can pass the physical exam... or whatever it is. I imagine the requirements for a mission like this one would be quite strict!"
"Hey, yeah!" Rainbow said. "I totally forgot. We're gonna need to line up a training regimen, so our crew is in top shape and ready to go." She looked thoughtful. "And I think I know just the pony to talk to about that..."