The Hitchhiker's Guide to the Galaxy has this to say on the subject of ponies;

Cute.

The concise, and indeed abrupt nature of certain portions of this compendium of knowledge is due in part to lack of space, but more to the total lack of competence, motivation and sobriety of the vast majority of the guide’s staff. The fact that races fairly similar to ponies inhabited a fairly large portion of the galaxy only increased the irrelevance of any entry on ponies.

"Why write about what people already zarking know?" as Stagyar Zil Doggo said to the unfortunate writer who had suggested perhaps writing a more suitable article. The fact that a major type of life form fails to get an entry over one word, while articles on far more obscure, if interesting, subjects can run to the thousands of words tells rather more about the guide than most staff would want to be known. The article on Equestria for example, despite being only a single land on a single world, is quite long, whereas none of the millions of races that are sufficiently similar to ponies to be called that, warrant so much as a footnote.

More popular than the "Celestia's Homecare" omnibus, better selling than "Fifty-Three More Things to Do When Trapped in the Moon", and more controversial than the infamous "Cupcakes" fanfiction, this wholly remarkable book has the rare distinction of existing in almost all layers of reality. In almost no way of looking at The Whole Sort Of General Mish-Mash (as it is technically known)  is there not a guide for seeing the marvels of the universe, surviving fantastic encounters with horrific monsters and finding the nearest and cheapest intoxicants. But like so many things, the story of the book can be traced back to some remarkably unremarkable people. A group of ponies from Equestria were some of them, but at this moment in time they are utterly unaware of their destiny, even for the next five minutes. It is possible, were they to know their destiny BEYOND the next five minutes, they would have given up on the entire thing.

The fact that one among them was not of the same species as the others had not occurred to any of them. Well, it had actually, but none of them had given it serious consideration. If any of them had done so, they might have become convinced. She took great care to seem like a normal earth pony, but she was about as competent at this task as any other roving writer for the aforementioned guide would be. Luckily, the others quickly learned to dismiss any odd behaviour as "Just being Pinkie Pie".

*

Sugar Cube Corner was silent at present. Well, almost. A single tired Pegasus stumbled out of the front door, eyes half closed. She tossed her rainbow mane out of her eyes, and immediately regretted it as the headache that had so far only been knocking politely on the front door of her mind, now barged in and demanded to know exactly how much she had drunk last night. Carefully, she stepped back inside.

Water. Need water.

As she attached herself to the tap, another blurry shape came down the stairs. She focused hard, trying to remember what orange was, and what this indicated about the pony joining her.

"Mornin' Sugarcube"

"Gnuuuuh"

Applejack stared at her friend, who was obviously in no mood to converse. She was made of sturdier stuff than her rainbow maned friend, and was one of those ponies capable of knocking back an almost fatal dose of alcohol and suffering next to no ill effects. She leaned against a wall, watching as Dash pulled away from the tap and sat on the floor, apparently now more ready to deal with the world.

"Where are the other guys?"

"Well, Twi's asleep on Pinkies bed, ah don't think she's gonna be too badly off. Pinkie's just stirrin', an' if I know her, she'll be feelin' friskier than…" Before Applejack could summon a suitably descriptive phrase, a pink maned ball of confusion came flying down the stairs, pushing ahead of it the startled bodies of Fluttershy, Twilight and Spike. Rarity followed a moment later, obviously having had just sufficient time to do her hair effectively, clean her makeup and even evade the party pony. Before anypony could open their mouths to forge a sensible conversation, Pinkie took the stand. She looked unnaturally serious, and they all remained silent, as she paced around.

"Ok you guys, I have to tell you the most important thing you're ever going to hear, I have to tell you now, and I have to tell you while you're all sitting down because it's super duper important but kinda frightening and I don't want anypony to fall over or anything and I know that you're all probably thinking this is just Pinkie being Pinkie and although I'm still Pinkie and I'm going to be Pinkie for the rest of my life I am not just being Pinkie here when I tell you I wasn't always Pinkie."

The others were all fighting internal battles on the twin fronts of Not Letting Your Face Show Amusement and Following What The Hell Pinkie Just Said, with varying degrees of success. Dash was fighting yet another battle, the hard front of Not Giving Up On The Entire Concept Of Living. She rallied sufficiently to enquire what the hell she, Pinkie, was talking about, and how she, Pinkie, expected her, Dash, to listen properly when her, Pinkie's, voice was both several octaves higher than was comfortable for her, Dash. Especially when she, Dash, was seriously considering going straight back to her, Dash's, bed. The others concurred, but without resorting to the multiple expletives that have been left out for decency’s sake. Seemingly unfazed, Pinkie continued.

"What would you guys say if I said I wasn't actually raised on a rock farm?"

Twilight scoffed a little. "Frankly Pinkie, I’m surprised that you expected us to believe that in the first place. Rocks aren't like the weather, they happen without ponies helping out."

"I mean, what if I said I wasn't from Equestria? I mean if I said I actually just came here one day and got stuck and then never tried to leave because I was just having so much fun and then I met you guys and everything was so great and I couldn't tell you because then you would think I was a big lying liar pants and you wouldn't wanna be my friends anymore? What If I said I actually came from a planet just a teensy bit away from Betelgeuse?"

Silence filled the room. The silence hung around for a few moments, waiting to be ejected from proceedings. Twilight was looking Pinkie in the eyes. She felt, as the only one who knew exactly what Betelgeuse was, she should have a little more to offer. Applejack had gone slack jawed. She knew a lie when she saw one, and this wasn't one. Dash was wondering if she had heard the pink pony correctly, or if she had just missed several steps in the conversation. Rarity was gearing up to comment, but it was Fluttershy who broke the silence, which by now had begun to feel awkward with itself.

"Um." Pinkie peered at the pastel pony, who screwed up her courage and said in a small voice "why are you telling us now?"

Pinkie gave a little yelp.

"OOOH! Because the world is ending in two minutes!"

The ponies stared. The silence which had only just been ejected from proceedings slunk back in the door, and settled itself down for a long stay. It was rudely turfed out by an unexpected sound from somewhere above. It was a voice. It spoke equine in a manner likely to cause the most hardened, deafened and possibly even dead pony to cringe in horror. It was a voice with nothing good to say, and no inclination to even try. It echoed around the the room, seeming to come off of every surface.

"People of Equestria, your attention please, this is Prostetnic Vogon Jeltz of the Galactic Hyperspace Planning Council. As you will no doubt be aware, the plans for development of the outlying regions of the Galaxy require the building of a hyperspatial express route through your star system, and regrettably your planet is one of those scheduled for demolition. The process will take slightly less that two of your Equestrian minutes. Thank you very much."

All six ponies dashed outside, dragging Spike along, who for his part had remained stunned for the duration of the previous events. All over Ponyville, ponies of all kinds were staring directly upwards. Hanging silently in the sky, huge, yellow, metallic and with absolutely zero regard for aesthetics or its own weight, hung something.

 It was not quite cubic, with every last part of it somehow contriving to utterly fail to please the eye in a new and unpleasant way. Where it should have been clean it was dirty, where dirt would have reduced the nastiness, it was polished to a shine. Rust clung like some hideous creature to corners, large enough to be visible even from ground level. Rarity almost fainted dead away. Ponies did not have radio, so there was no voice to answer this challenge to their existence, and the Prostetnic Captain, slightly dissappointed at not being able to lecture the planet below and get himself properly angry, pressed the button, set to Rubble.

 The sound was almost as unpleasant as the ships had been, for there had been hundreds, thousands, positioned all over the lonely planet with its own orbiting sun and moon, which now flew away into space as the planet they had served ceased to exist. The sun would go on to collide with a large meeting of record company executives, which just goes to show that all events have their bright side. For a moment, an after image of the planet hung in the sky as a perfect sphere of yellow chunky ships sat still. Then they peeled away, leaving nothing behind. And so the end of the world happened. Slightly ahead of schedule, which would at least give the captain something to write on his reports and get angry about.

Really, very little of this story was ever gong to concern Equestria, better to hurry on without getting bogged down.

*

The Hitchhiker's Guide, in a moment of surprising clarity, mentions that the minds of most races are simply not geared to deal with certain events, especially large-scale tragedies, and anything at a distance. Very few beings are capable of considering more than 10 or so deaths without just filing the event at the back of their mind, marked under "Do not open". They will be aware it is a bad thing, but will not feel it on a personal level. One race which, by some quirk did not gain this ability to write off tragedy, are the Mardajons of Lepluss. They are solitary purple creatures which spend almost all of their lives paralysed with grief, as they feel every single tragedy as if it were personal. Their economy subsists almost entirely on the production of dark corners to sit shaking in, paper bags to hide from the world in, and military grade intoxicants of all kinds. This simply goes to show that while evolution is the driving force behind all life in the universe, it can mess things up just as well as an inattentive god. The only reason the Mardajons have yet to die out completely, is that solace is often enough sought carnally, and the Mardajons, by another quirk of nature, happen to be frightfully good at breeding. This is a shame, because a nice clean extinction would be a boon to them all. The guide goes on to explain that the Mardajons were particularly grateful when conservative politics were invented, as this enabled them to stop caring about others at all.

*

Thus it was that our six ponies and one baby dragon were not as fazed as one might have thought. This event was simply too big to think about. Another reason that they weren't upset right at this second, was that they were, with the exception of Pinkie, unconscious. She had been through a matter transference beam before, and took the opportunity to think. Had it been a good idea to get them all drunk last night? Admittedly she had barely woken up in time, but all in all she had learned that a hangover had the effect of causing enough self pity that a pony could ignore almost anything; the body ignored everything other than its current misery. And how else could she have brought them all together? Well, maybe one of her ordinary trademark Pinkie Parties, but since the magic of alcohol had been discovered by the group, any party generally gravitated towards the stuff. Besides, it had worked right? It was a shame she couldn't have brought more, but even seven beings was stretching it for something done without the Vogons noticing and locking them out. As it was, they had arrived intact in a rather squalid, but currently unoccupied sleeping quarters. Thank Celest... well, thank somepony for the Dentrassi. Without them, hitching a lift with Vogons would be impossible on a very VERY good day, and suicidal on all of the other days. She peered into her bag, making sure she had everything she needed. In addition to the electronic thumb she had used to hitch a ride, she had her towel, her sub-ether radio, which she had used to pick up news of the arrival of the Vogons, and that most remarkable book, The Hitchhiker’s Guide to the Galaxy. Sighing, she scrolled down to the entry on Equestria. Magical places had unnaturally rapid updates, as revisions could be beamed from the future when the news finally reached the editor. She stared. Oh. This was going to be awkward to explain.

*

Back in the void left behind by Jeltz, a bright spark of light moved around, trailed by another purple one. Slowly, a worldlet formed, growing. Water bubbled up, creating seas and lakes, mountains sprouted like snowy spines and grass coated the planet. Had anyone looked closely, they would have seen towns, roads, houses forming. A tall white alicorn followed by a smaller purple one strode along, and life spread out from them in ripples. Ponies frozen in the act of peering upwards were magicked back into existence, an orbiting sun and moon formed above, spinning gently. Backup restored.

*

“So, just one second Sugarcube, why exactly can’t we go back?” Applejack’s voice was patient, barely.

“Weeeell…” Pinkie bit her lip. “Apparently Celestia is so super duper powerful she could have just remade the whole planet around us again and we wouldn’t even have noticed. And she did, including everypony there. Everypony, and that means us. We’ll have been brought back to live out our normal lives and we can’t exactly go back, I mean how weird would that be, there’d be two of me and although that would mean really super awesome parties and some great pranks and all sorts of…” She looked around as the clanging of boots sounded in the hallway. “Also, it looks like the Vogons have found us and are almost certainly going to be really mean and throw us off the ship and I really don’t think we can persuade them to turn around and drop us off.”

Rainbow Dash facehoofed, the others just stood dumbstruck. As large green shapes came through the door, only Applejack could say anything.

“Oh horseapples”

*

Vogon fanfiction is without doubt at least the second worst fanfiction in the known universe. It is written with the express purpose of making the author feel happy, and when the author is a large, slug-brained, bloody-minded, petty, vindictive and generally unpleasant bureaucrat, this results in something truly horrifying. And it was to this that our unfortunate heroes were now subjected. Vogons know exactly the right fiction to bring out to really upset their guests, and so Jeltz had brought out his four thousand-word epic on his ponysona, and how it had saved the universe.

“… And so Jeltz Embersparkler stormshadow rainboomer tosed his chaging colured mane and it flowwed like changing rainbow fires over his enormous sexy wings and his horn split it down the middl like a horn splittin fantastic sexy hair cause thats what it was…”