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       Celestia and Luna's Ultimate Space Adventure        
                       -by ArtHeart-                       
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                      A Trip to Space                      
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A Trip to Space
Princess Celestia, after raising the Sun, started her general work day of doing her taxes and writing letters. As she first got started, she suddenly heard a noise from the opposite hallway.   
"TIA!"  
It was her sister, Luna. Celestia knew by instinct that when Luna calls for her assistance, it is no serious emergency. It would just be either asking for extra bits, or challenging her to a cake eating contest. Although she did love cake, it wasn't the time right now.
Celestia headed to Luna's room, to ask what she desperately needed at the moment.  
"TIA!" She yelled. "Since I have no tasks on my schedule, I thought we could pay a visit to my old home, THE MOON!"  
"Luna," Celestia added. "I know how you are with the Moon, but wouldn't it be a little boring with nothing on there?"  
"Don't worry, sister," Luna responded. "I left something behind before I left, a telescope to be exact."  
"Let me guess, to watch Earth?"  
"YES! And now I can watch the Moon with it! So, can you come?"  
Celestia knew it was a no. With all the busy things she had on her mind, she couldn't possibly do a ridiculous thing like visiting her sister's old "home." It would break Luna's heart, but she had to do it.   
"Luna," She said. "We can-"  
"PLEASEEEEEEEEE!" Luna whined.  
"Ugh.... guess it couldn't take too much time, and I'm sure Twilight won't mind that i miss a letter for one single day," She thought.  
"Alright Luna," Celestia spoke. "We can go after I write a little bit."  
"HOORAY!" Luna yelled. "I'M GONNA PACK!" She rushed to her closet, with Celestia heading back to her throne.  
...  
When Celestia returned, she began to write to Twilight about their little "trip", and they would be absent for a few hours.
Dear Twilight Sparkle,  
My sister and I have decided to take a trip to space for awhile. Don't worry, Equestria will be safe. I hope you can understand our absence, and will   
return when we are done observing the Moon.  
Yours Truly,  
Princess Celestia
A short letter, but that would have to do for now.  
...  
Luna appeared from one of the many corridors from the castle, running to Celestia.  
"I'm ready!" Luna announced. "Let's get moving!"  
"Alright.." Celestia said. "But how will we arrive?"  
"TELEPORTATION!" Luna yelled once more.   
"What are you-"  
Before Celestia could speak, Luna teleported both of them away from the castle straight to the Moon. They both jolted in the illuminating light from the overwhelming magic, and then disappeared on their way to space.  
But the letter was also left behind on the floor.
MEANWHILE, IN PONYVILLE  
...  
"SPIKE!" Twilight yelled, shocked at the same time.  
"Celestia forgotten my morning letter, and that means she missed the time, AND THAT MEANS SHE'S IN TROUBLE!"  
"Calm down, Twilight," Said Spike, after just awakening from a good night's sleep. "Just because Princess Celestia doesn't send you a letter every morning, doesn't mean that she's hurt."
Twilight ignored him, and went on. "THIS. IS. A. DISASTER! I know what I must do."  
"Read and look for an answer?" Asked Spike.  
"No," Said Twilight, suddenly getting more parinoid than once before.  
"I'M GOING TO TAKE OVER!"  
...  
Luna and Celestia saw themselves among the cold, hard surface of the moon. Celestia was shivering from the low temperature of -27 degrees, but Luna was trotting around with pleasure at the sight of home sweet home, at least for a while.  
"Well, dearest sister," Luna began. "Welcome to the little prison you decided was right for me for 1000 straight years."  
"As if I had any other idea," Celestia spat back. "If I didn't think quickly, I would've been KILLED!"   
Luna smiled nervously, then walked on with Celestia by her side.
Luna rememberd that Celestia had set up a room on the Moon when she was trapped, as Celestia remembered that she needed to survive. So she asked her sister if she could use it again.
"Tia," Luna spoke. "If it isn't too much of your time, may you use your magic to set up my old room?"  
"Well....." Celestia said. "I guess I could deal with it. Okay, get ready...."
As Celestia used her powerful magic with an aura of golden light around her horn, made a hollow space appear before them with blue walls. With a moon symbol on the front, they could already tell that it looked just like Luna's old room.
"I...I LOVE IT!" Luna shouted, overfilled with pleasure. "It's just like the old days."  
Luna went inside the room, while spawning in a bookcase filled with hardcover encyclopedias, mostly on the stars and space. Adding to that was a bed with purple sheets with stars, and a bat pony plush on her nightstand with a lamp.   
"Sister.... I can't possibly thank you enough," said Luna, directly making contact with her sister.   
But then she got a thought. It didn't feel like home just yet, there was one thing missing: isolation. This means Celestia would have to be on the edge of the moon, waiting until Luna was done with her fun.
"Celestia," Luna asked. "Could you move to the outside of the moon for one second?"  
Celastia had an uneasy feeling, but agreed. "Alright, sister," she replied.
As soon as Celestia backed away, Luna used her powerful magic to emerge a forcefield among the edges of the stone cold surface. Luna smirked at her pleasant idea, with her sister getting angry at her isolation.
"SISTER!" yelled Celestia, frustrated with tension at the smiling alicorn. "DO YOU THINK THIS IS FUNNY? I HAD TO GO THROUGH THIS FOR 1000 YEARS!"  
"Exactly," Luna said in response. "It just doesn't feel the same with you around, so this happened!" Her lips were curling into a smaller smirk and breaking into a small pleasant smile. Celestia was angry, and flew away to the direction of the sun. Luna saw the flight of her sister, and wondered where she was going.
"Sister?"  
...  
Ponyville was in huge terror when the bakery set on fire. Apparently Twilight thought it was a good idea when she told Pinkie Pie to overheat the cupcakes so the princesses would locate the screams of the ponies. But that plan had failed, and Twilight was parinoid even more as time went on.
"The princesses should be here any minute...." said Twilight nervously. Her mane was starting to tangle for stress and fear. This was VERY important to her, and she wouldn't let herself down.  
"Twilight," Spike told her, when snapping back to reality. "Maybe the princesses are busy somewhere else, and don't have the time to send letters each and every morning."
Twilight simply ignored Spike's advice, and babbled endlessly about the possible outcomes this could lead to. "SPIKE! THIS. IS. SERIOUS! WHAT IF THE PRINCESSES HAVE BEEN KIDNAPPED BY TIREK OR SOMBRA! OR MAYBE GOT LOST IN A SECRET CAVE! OR MAYBE-"
"SNAP OUT OF IT!" Spike yelled. "If you want to see the princesses, why don't you head on over to Canterlot?"   
Twilight admired Spike's advice, and agreed. "Spike, you're a genius! Now I can see what all the trouble is!"  
The pair started running over to the train station, not wasting a minute more to pack anything. They took the nearest train to Canterlot, and we're off to see the princesses.
...  
Celestia eventually returned to Luna's location, with a humongous round orb of fire behind her. With Luna shocked, she was lifting the Sun up with her magic. "THIS IS TO PROVE TO YOU THAT THE SUN IS A STAR!"
Luna quickly remembered that in her childhood she had talken part in many arguments that the sun was a planet, not a star. She had learned that the sun is a star, with those memories behind her. Celestia was being ridiculous, but still moved the sun near her, melting the forcefield. The moon was starting to catch the flames from the sun, causing mini flames to crawl over the surface.
"TIA!" She shouted. "YOU DONT KNOW WHAT YOU ARE DOING! I HAVE MOVED ON NOW!"
Celestia ignored her, and moved the sun closer, causing Luna to start to sweat. As the sun moved closer, Luna blocked it with a magic barrier. But it wouldn't last long. It eventually faded, and she had no weapon of defense. Watching her room burn before her, she started to run among the rounded edge.
When she ran out of energy, she knew this was her last breath. The sun came closer, and Luna closed her eyes, waiting for her death to come from the sun goddess. It got very hot, until Celestia stopped and shouted:
"GOTCHA!"
The sun moved back to its original position, and Luna stood up on the ground. She spoke in complete shock. "But... But you were going to demolish me in flames!"  
Celetia turned back to the navy blue alicorn with a smile, pleased with herself. "Luna, us princesses have our fun sometimes. We are not just proper and uptight, we are normal ponies. Besides, why would I burn the best sister in all of Equestria?"
Luna's frown broke into a smile, hugging her sister and forgave her. "It's alright, Tia. Now let us return home."
With the translucent blue aura glowing around Luna's horn, the two princesses dissappeared from the moon, coming back home in their castle in Canterlot.
...  
Twilight and Spike ran through the castle into the throne room, seeing no signs of the princesses. Still paranoid, Twilight scanned every inch of the room looking for objects. She found a written note beside Cesestia's throne, reading it to Spike. After she was finished reading, she regretted everything she had went through.
"Oh, Spike," said Twilight with shame. "I'm such a fool! I should've known they were someplace else."
Twilight's wails were interrupted with Celestia and Luna coming in from a bright blinding light overcoming her. She broke into a great grin, happily running over to both of them.
"Celestia! Luna!" She squealed. "I'm so happy to see you both! I thought Equestria was doomed! I'm so naive for thinking you two were trapped somewhere instead of a trip to the moon."
Celestia looked to her side, noticing the note she had written for Twilight that morning, realizing she had not sent it. "I apologize for the misunderstanding, Twilight. We were in a rush." She came over to Twilight's side, giving her a gentle look of sympathy.   
"I forgive you, Princess," said Twilight. "I hope you don't mind if I took over Ponyville for a bit."
Celestia looked outside to see Ponyville in a disasterous outbreak, assuming Twilight had caused it. She glared at Twilight, with a disapproving look. With Twilight having a nervous smile on her face, she flew out into the distance to fix Ponyville to settle the outbreak of fear.
With the two sisters making eye contact, they both laughed and headed to their duties happily, never forgetting this wonderful day they had shared with each other.
Author's Note
Thank you so much for reading, and feel free to do an audio version! (You can use the artwork above)  
:trollestia: https://static.fimfiction.net/images/emoticons/trollestia.png