NASA has a wonderfully evocative series of 14 posters illuminating a grand tour of the solar system, shown at

https://www.jpl.nasa.gov/galleries/visions-of-the-future

They are free to use, designed to be printed at a 20 by 30 inches size, and could be printed and placed on the wall in a poster frame. They might be something that she could grow into over the years, perhaps starting first with one in her current favorite colour scheme?

I feel that they capture a wholesome and optimistic view of exploration very well, and are inspirational.