Usually she'd put comparatively little stock in millennium-old legends, but this is a primary source, and the authors made some correct predictions on other matters, and the translator is good, and she double-checked to make sure the page numbers matched up so no one has been pranking her with inserted extra leaves. And the prediction is fairly dire.
And it's rather short notice.
Clarity tucks the book into a saddlebag and trots up to the main section of the palace. She can usually get an audience fairly quickly; Celestia has taken a particular interest in her since her admission to the School for Gifted Unicorns. This day is no exception. In fact, the guards usher her in even quicker than she'd usually expect.
"Princess, I have something urgent to tell you," Clarity says, mid-bow.
"Oh? What is it, Clarity?" inquires Celestia.
"I've found a prediction stating that on the longest day of the thousandth year -"
"Clarity," sighs Celestia.
Clarity grits her teeth; she's never told Celestia not to interrupt her. You can't tell the princess that. "Yes, Princess?"
"I have the utmost respect for your diligence at your studies, but you've got to take your nose out of those dusty old books now and again," says Celestia with a warm half-chuckle. "There's more to a young pony's life than studying. You're in the prime of your life, you're coming up on the end of what you can learn from school -"
Clarity stands up on all fours, no longer bowing, jaw slightly open.
"And," continues the Princess, "you need to make some friends. I worry about you all alone, you know. Weren't you invited to that party - who was it, Moondancer?"
"Yes, I was invited, but I barely know her," says Clarity.
"Perhaps the ponies around Canterlot just aren't clicking with you. You know what," says Celestia, as though seized with sudden inspiration. "I'm going to give you a job to do."
"...a job, Princess? But what about the longest day of the thousandth -"
"Clarity," says Celestia again, and Clarity shuts her mouth. "Don't you worry about it. I'm sending you to supervise the preparations for the Summer Sun Celebration. It's being held in Ponyville this year. I'll arrange a carriage for you. Pack your things, you leave in two hours."
"I..." Clarity can't really gainsay her. "Yes, Princess."
Celestia smiles.
Clarity bows again, and leaves, and packs.
-
She's in the air, drawn with her luggage in her carriage by someone in good condition for a long-distance flight - they're still working on that train line.
She steps onto the main street of Ponyville, laden with all her possessions in her saddlebags, and levitates her to-do list in front of her nose.
"Okay," she sighs to herself, peering at the first item. Clarity is pretty sure Celestia has read every book in the palace library at least once; probably she investigated the danger well in advance and dismissed it. (But Clarity will be staying in a library while she's in Ponyville, so she'll have a chance to double-check and find corroborations once she checks out the Summer Sun Celebration preparations.)
"First," Clarity mutters, "banquet preparations. Cheery Cherry Orchard."
He giggles. "You know, it's funny, but not everypony manages to figure that one out. What's something fun you've learned?"
"I can teleport! There's a range limit and I have to see or know details about where I'm going, or I'd have gotten all the way to the orchard myself without the carriage, but I can do it under the right conditions and I'm working on those constraints."
"There's also a little problem with momentum - it's more complicated to cast the spell if I'm moving and I can't land with momentum attached to me at all. Obviously Celestia can teleport any way she likes, but it's a worthwhile exercise to figure out the details myself as long as I don't need to do particularly sophisticated teleporting for some kind of emergency."
"Orchard's just down the road!" he says, pointing - there are indeed cherry trees coming into view around the next bend.
"You're welcome!" His tummy rumbles; he glances down an upcoming fork that leads away from the orchard and into some rocky hills. "Now I really better go grab lunch. See you later, Clarity!"
Clarity trots sedately towards the cherry trees, looking for somepony who appears to be working on catering the celebration.
"Hey there!" she says affably. "Cherry Cordial, at your service. What's your business in Ponyville?"
"I'm Clarity Bell, and I'm here because the Princess asked me to oversee the preparations for the Summer Sun Celebration. My list suggests you're in charge of food; how's that coming along?"
She kneels down so the raccoon can climb onto her back. He does that, then waves cheerfully to Clarity as Cordy straightens and turns up the path towards the farmhouse.
Clarity waves a forehoof at the raccoon and then follows Cordy. "Do you prefer Cherry or Cordial? I'm guessing Cherry is a family name?"
"Good guess! I go by Cordy," she says. "Cordial's fine too. My aunt Cherry Crash goes by Crash. And this is Sebastian, my secretary." The raccoon smiles.
"And I usually go by Clarity, but I'll answer to Bell and it's not a family name. Is there a lot of secretarial work around a cherry farm?"
"I like to be organized. And I'm not just a cherry farmer; I also take census for all the miscellaneous creatures around Ponyville."
"One's the family business; the other's my talent," she explains. "I can communicate with anyone and anything. So it just makes sense that I should be the one to count them all."
"Statistics. Records. If there's a hundred new bunnies born every year for three years and then one year it's only fifty, that probably means something's affecting the bunnies, and it might be a good idea to find out what. Things like that."