Dear Princess Luna and Princess Celestia,
Over the course of the last day, I have had many conversations with our visitor from the stars - thanks to the amulet you supplied, Princess Luna - and we have already started to learn much about each other.
Moongleam - as she lets us call her in Equestrian, a translation of the last part of her full name, "Cordelia Vintar-ith-Vidutar Iriselen" - has been friendly and courteous throughout our exchange and to others she has met, despite the wreck of her starship - which she has been kind enough to presume an accident, assuming that we did not know that it was never designed to land - the fortunately minor injuries which she sustained in the crash, and the stress of her current circumstances. I am confident we need have little fear of any hostility on her part.
I have as yet learned little of the Empire from which she comes - an incredible multi-species union of nearly 300 worlds - but it's clear from those devices I have seen myself, as well as their ability to cross the stars, that they are technologically far ahead of us. On the other hand, they don't seem to have - or only have very limited - access to magic. Moongleam seems fascinated by Equestrian magic and its possibilities to revolutionize their understanding of the world, as fascinated as I admit I am with their machines, and she seems entirely willing to share their knowledge - beginning with giving me free access to the library she brought with her, a library of millions of books!
Others of Moongleam's revelations, however, are both inspiring and terrifying - especially since they seem to come as as much of a surprise to her as they did to me. The food, and many of the plants and animals of our world, are familiar to her, and from a depiction in her ship, her people have legends of creatures very similar to unicorns! The existence of some connection between our worlds, possibly even common ancestry, seems inescapable.
This could be the greatest opportunity in Equestria's history - or the greatest disaster, if things go badly. I'm not sure I should trust my judgment about this; I want it too much. Could I talk to you both, either here or in Canterlot? I really need your advice.
Twilight Sparkle,
Bearer of the Element of Magic,
Daughter of House Twinkle
That's some surprising restraint coming from lavender horse. But it fits
Good to see she recognizes that immense change is coming. Their civilization is about to be introduced to the galactic stage; no way around it with how many parties will want to study them, and having been gifted knowledge of technology centuries more advanced than their own.
Cordelia was self-levitating earlier. Doesn't that mean she definitely has limited magic access?
I get this image of TwiFly going, Heeelp Meee. So much information.

7744978 I imagine she got gently scolded the first time she sent a letter to Princess Celestia that consisted solely of six pages of "YESYESYESYESYESYESYES!"
7745134
Depends who you ask. If you ask her, as of now, she'd tell you that what she has are internal nanomachine-sized vector-control effectors that let her do a variety of interesting things with gravity, but there's nothing magical, in any supernatural sense, about them. Any more than there is about, say, electricity.
(That Twilight perceives her using those as feeling similar, per last chapter, to a unicorn's field, is itself somewhat interesting in this department, of course.)
But then, as we know, any sufficiently advanced science is indistinguishable from magic (Clarke), and any sufficiently analyzed magic is indistinguishable from science (Foglio), so it's really quite fortunate that we have for our protagonists a couple of geniuses who are more than willing to Do Research To It, no?
A lot of research.
This is delightful thus far. It's surprisingly hard to find good sci-fi on this site. I always appreciate it when I can. Eagerly looking forward to more.
7746970
Nice use of Heterodyne's corollary. It's a maxim I'm rather fond of, myself. Looking forward to some magitek and magical science!
8763584
I did not know of the Sage Heterodyne, but his words have always been implicit to me in light of Sage Clarke's oft-quoted maxim! I thank you for the name reference for future use!
7746970
Ooo, imagine Agatha and bookhorse meeting...