Transcendence. My story idea. Tips and Ideas please?

So today at school I had an idea.

For a story.  and here it is.  And please give me tips and some ideas and whatnot:::::::

Well, so Transcendence is basically about this girl, trapped in a celestial prison.  She basically is trying to escape it, while trying to stay alive in it, without getting caught.

I don't have a name for the main character yet either, so please give me some ideas.  I want it to sound galaxy like, or celestial like.

And I still have only the major plot line layed out.  PLEASE HELP!!!! I can definitely use it.

Anyway....

So here are some ideas for the name:

Estella

Astara

ya thats it.  

I would love ideas!!! If you have any that would be amazing, especially about the prison camp she lives/works/is imprisoned at.

Well........................... 

Have a good week! 

Bye!

"The three stars painted on her wall, hidden by the cold metal burning into her vision.  She was ready, ready for the.....

The cold metal slammer door's thunder noise filled the room.  She turned her head, just to see the Admiral, the Admiral, captain of the prison camp, walk into the room.

"_____, You're coming with me."

-Just made up chapter I made up right now for this story :)