Each day Earth heard the message, always at the exact same time, regular as clockwork.

The first message had come six days after the disappearance of Phoenix and Mark Watney with only a vague, interrupted message from the aliens to account for it. The voice of the pony Starlight Glimmer, a bit muffled and nasal, had echoed around the world after its release by NASA.

“Greetings to the people of Earth. This is Starlight Glimmer. I’ve recorded this message for a space probe we’ll send to your world once per day until (achoo!) Mark Watney returns. Mark’s here with us in quarantine on our home world. We’ve all caught cold, but the medicine is helping, and other than that we’re all right.

“Our probe can only remain in your universe for ten minutes. Then it has to come back or risk being stranded forever. So our time to communicate is brief. We will send you a message on this frequency. The probe will record all transmissions sent in analog audio to our Channel Four, which NASA has in the records of our early communications attempts.

“For this first window, we don’t expect a response. Tomorrow, however, our doctors would appreciate anything you can send about Mark Watney’s bone and muscle mass and his eyesight. They’re performing tests on all of us to see how we are after so long on Mars. Thanks in advance, and we’ll be talking to you tomorrow.”

As promised, every day a new message followed the first, read by either Starlight Glimmer or Dragonfly. The first part of each message usually consisted of some request for particular information- information about Mark Watney and human health issues, information about Hermes, information about computers, and so forth. Then any questions that Earth had sent up the previous day would get answered, up to the ten-minute limit.

And then, if there was any space left on the recorder, a message would be added from Mark Watney. It took several days before the first of these appeared, but by the tenth day they became a regular part of the message:

“Hi Earth! Mark Watney here! Today I visited Cherry Berry’s workplace, the Horse-town Space Center. Not to be confused with Ponyville, which has a castle but not a space center. Anyway, HSC looks remarkably like Kennedy back home. What’s amazing is, five years ago this was swamp, and now it launches a manned flight every two weeks or so. But NASA be warned, when you come here you’re going to need to take some tranquilizers. Gotta go!”

“Hey, it’s Mark again! Mark Watney. Remember me? I used to be stranded on Mars, farming in a crystal cave. Well, today I saw another crystal cave, under Dragonfly’s home. It’s not as spectacular as Salvation Cave on Mars was, but it’s really pretty, especially by torchlight. Of course, a couple thousand changeling eyes watching me all the time is a bit creepy by torchlight. Hope to see you all soon!”

“Mark Watney here. I only have a few seconds, so I’ll just say one thing. I have eaten the cake. ALL the cake. Real, actual, genuine, zero-potato-content cake. And it was delicious. Later!”

“Hey, this is Mark Watney! And I’ve got a question for my buddies on Hermes; what kind of souvenirs would you like? I’m going to be doing some shopping soon, and I’d like to know what kind of stuff you want from the pony planet. Pass it on, okay NASA? Thanks!”

“Quick message from Watney: ponies play golf. Same clubs, same course, same rules, just like Earth. The word is even the same. Chalk up another point for parallel world theory.

“What’s more, the ponies play golf without magic. And they don’t hold the clubs in their teeth, either. They stand up on their hind legs, hold the club in their fetlocks, and swing just like a human. They tend to fall over a lot, not so much like a human. But they still play better than I do. And I still don’t see what people see in this sport. It’s just an excuse to wear ugly clothes and tear up a lot of sod and grass. But that’s just me. And it has nothing to do with me chalking up a thirteen on the first hole while Spitfire makes her birdie putt.

“Anyway, let me just leave you with the mental image of Fireball in knickerbockers and a plaid beret with a little red puffball on top. He hits monster drives, but he can’t putt for shit. Anyway, later!”

And then, one day, the messages changed: what had been a minute or so of Mark Watney became the whole transmission.

“Hello, Earth! This is Mark Watney. Looks like my little vacation is over. The ponies are currently getting ready to return me, so I’m getting ready for my flight back into space. I’m also being trained for something else, but the rulers here asked me not to say anything more about that until I get back. They want it to be a surprise. Gotta say, it’s one hell of a surprise, so I won’t spoil it.

“On to business. When the ponies bring me back, they want to put me as close to Hermes as possible. We need to verify a few things. Will Hermes’s attitude thrusters have enough juice to stop rotation for docking and then restart it later? For how long a timeframe can Hermes stop the VASIMR engines for docking without jeopardizing their return trajectory? If necessary, can Hermes dock with Phoenix if Phoenix has zero thruster capacity? If not, what’s the minimum requirement for Phoenix thrusters? That last bit we already hashed out for the Sol 551 launch, but they want verification.

“Now, to answer some of your questions. Yes, gold and gemstones are a lot more common here than they are on Earth. One of Starlight’s friends has a family that runs, get this, a rock farm. It’s like a quarry, except they actually do grow rocks there, too. It’s a specialized magic thing. I haven’t seen it myself yet, but I’m hoping to get a day away from my current top-secret activities to check it out.

“As for gold, there’s not much in the way of paper currency here. The main medium of exchange is a thick gold coin- well, gold-ish, about fifty percent by content, but it’s still over a quarter ounce of gold per coin. And it takes two of those coins to buy a large supermarket-quality apple. Granted, the apples here are the size of grapefruits, but that’s what? A thousand bucks worth of gold for one apple? I mean, the apples are good, but not a thousand bucks good.

“Anyway, I’m sorry if I stepped on some toes, but I already explained this to my hosts, and Starlight explained it to them before I did. And they won’t be letting people pack large amounts of gems or gold off with them to make it rich on Earth.

“As for what the ponies lack that we have, so far I’ve only found one thing, and I don’t think we’re going to be selling a lot of uranium to folks here. It’s so rare as to be almost nonexistent, but the only use they have for it is for physics experiments. And after hearing about us, they don’t want any large quantities of it here at all.

“Just about out of time for now, so I’ll be talking to you tomorrow. Tune in tomorrow, same Watney time, same Watney channel!”

And so it went, for a week and a half. Then came the final message:

“Well, launch day is almost here, so this is my last message home until the other side. In fact, I’m going to keep this one short, since my friends are giving me a going-away party in this world’s version of Las Vegas and Hollywood combined. Which is another flying city, like Cloudsdale, but it gets tons of non-pegasus tourists.

“Yes, I know this will disappoint you, but I said going-away party. My friends aren’t coming with me on this flight. The flight surgeons have them grounded. So everyone on Earth, you’ll have to wait a bit longer before you meet everyone face to face. The good news, though, is that we won’t have to go double-bunks on Hermes.

“Speaking of Hermes… Commander Lewis, believe it or not, the ponies both have thatched-roof cottages and house synth music. They also have magnetic tape, so I’ll be bringing a tape deck and a sample of various recordings. The ponies prefer vinyl, though, and the CD hasn’t been invented here yet, so the tapes will have to do. Martinez, I’ve got a book here all about Spitfire’s unit, the Wonderbolts. I’ve got a snazzy top hat for Johanssen and an Arabian-style veil for Beck- you can wear them at the wedding. And if anyone thinks I have those two mixed up, well, I know them and you don’t, so go f… I mean, so there.

“Finally, Vogel, your kids might be a little too old for them, but I did as you asked and brought you half a dozen pony plushies. I was even able to score a Cherry Berry, a Dragonfly, and a Spitfire. Unfortunately there doesn’t seem to be a market for Starlight Glimmer or Fireball plushes in this universe, so I bought one of the little alicorn princess, a griffon, and a unicorn. Hope your kids like ‘em.

“Anyway, my balloon ride’s waiting, so until I’m back in my home universe, this is Mark Watney, signing off.”

And the next day, the pony probe did not appear.

Nor the next, nor the next, nor for several days to follow.

“Hermes, this is Phoenix. Stand by to begin docking procedures.”

Every head on Hermes jerked up. Every hand dropped the normal daily routine tasks and scrambled to action stations. Thanks to all the messages relayed through the interdimensional space probe, they had known that, sometime very soon, the failure of Sol 551 would be made good. They hadn’t known what day, though, and they certainly hadn’t known it would be today.

“Commander to the bridge!” Martinez called over the intraship radio.

“On my way,” Lewis said. “Beck, Vogel to Airlock 1 and suit up.”

“Already there,” Vogel replied.

“Phoenix, Hermes,” Johanssen said from her station on the bridge, “message received and welcome home.”

“Thanks, Johanssen,” Watney’s voice replied from Phoenix. “Concordia- that’s Harmony- will stick around a few minutes to make sure the docking comes off. Also, I’ve been asked to relay a message. Stand by.”

“Roger, Phoenix,” Johanssen said. “Standing by.”

Outside, the immense Concordia released its claw and gently pushed away with its maneuvering thrusters, leaving Phoenix free to maneuver in space.

“Phoenix, ready for remote docking control,” Martinez said. “Uplink established.”

“Copy, Hermes. Message begins.”

There was an additional hiss over the radio, and then a new voice spoke, one the Hermes crew hadn’t heard before.

“To the people of Earth. Greetings from Equestria. I am Princess Twilight Sparkle.

“Thank you for your generosity and kindness in helping us bring our friends home. We know you were looking forward to meeting them in person. Unfortunately, the low magic environment they experienced in your universe made them very sick, not including the injuries they suffered during their time there. They need time to heal, to think, and to decide for themselves if they wish to continue being explorers in the greatest enterprise imaginable. And we don’t want to risk what happened to them happening to other ponies.

“So we’re sorry, but we’re sending Mr. Watney back to you alone. And we’re not coming to visit you, at least not any time soon.

“But maybe you can come and visit us.

“In addition to sending Mark back with a Sparkle Drive and extra batteries to speed Hermes on its voyage home, we have sent some experimental equipment. The experiments, if they function, will tell us whether your world has enough magic for us to visit long-term. Once this concern is dealt with, we can tackle the second problem, providing a simpler, safer way of traveling from one world to another than a rocket launch.

“With this end in mind we have also sent you a number of magic wands, which will allow humans to cast spells in the same way unicorns do. Mark has tested them, and they work. Although Mark will never be a great wizard, we have taught him a few basic spells, and your scientists can take it from there.

“We have also provided full instructions for construction of your own Sparkle Drive… along with video of some of the dangerous things we found while searching for your world. We don’t advise that you go exploring blindly as we did. The danger is real.

“But we have also included our own world’s coordinates in relation to your own. You will be welcomed as Mark was, should you decide to come- so long as you use this gift responsibly. Magic has many dangers and temptations, as many of us on our world have learned to our regret.

“Use our magic well. Use it wisely. And use it together- in friendship and harmony.

“Until then, we will resume our communications via the Angel 18 interdimensional probe. We look forward to your questions once Mark and his cargo are returned safely to your world. Until then, farewell.”

There was a long silence. “Is that it, Mark?” Martinez asked.

“That’s the message,” Watney replied. “Ready for remote docking. Secondary thrusters at ninety-nine percent. Primary thrusters still at zero.”

“That was their princess?” Martinez asked.

“One of ‘em,” Watney said. “They have several. The idea is, having one queen causes trouble, but you can have as many princesses as you want.”

“Obviously they have not read Earth history yet,” Vogel said from the airlock. “Else they would not be so optimistic.”

“Yeah, yeah,” Martinez said, “but what I want to know is, how did she learn to speak English that well? How long did she have to learn it, Mark?”

“I dunno, maybe a week, week and a half,” Watney said. “Starlight was with me most of the first three weeks I was there, so I don’t think Twilight would have been able to start before two weeks ago.”

“She learned a language like English in a week and a half?” Martinez asked. “That’s scary, man.”

“She might have learned just enough to be able to read a phonetically prepared script,” Lewis said, taking her seat on the bridge. “Not impossible.”

“Guys, I really don’t know which it was,” Watney said. “But could we get this ship docked? I’ve got a lot of luggage to transfer, including a slightly used warp drive.”

“Sorry, Phoenix,” Martinez said, all business once more. “Remote uplink confirmed, beginning docking maneuvers.”

And as the MAV was carefully guided toward Hermes’s vehicle air lock, Concordia vanished.

Author's Notes:

Two chapters left.

EDIT: My original idea was that this would be the end of all contact between the two worlds for the time being. However, I decided for whatever reason to have the ponies use the same probe they used to confirm Watney's dimensional coordinates to get medical and other information from Earth. And then, when I got better enough to write, I decided, "no, there's just no way they'd shut this line of communication down cold."

So, instead of just having Watney appear, I expanded this scene by referring to the messages sent through the probe. Which, in turn, allowed me to fill in a couple of gaps in the previous chapter.