Great book if you are looking for a book with well presented facts, easy to follow and decent images. My 5 year old absolutely loved this book. He doesn't read yet so we need a balanced amount of text/images on a page. In fact, they did a great job with the images as there's quite a bit happening on every page, really supporting the text making it very easy to follow. He's had it for a year now and he still comes back to that book which is great I still enjoy reading it too.
He also liked the size of the book and prefers it over the A5 size smaller books on the same topic.
Some similar books are bigger on referencing web links for additional information - which in our experience is a completely overrated feature. He doesn't read yet so google moon and navigating the nasa website was sufficient. And in the future I would prefer he learns to think for himself and learn how to use google to find good sources rather than rely on out of date poor quality links. In fact we did try some of the links (from other books) and were very dissapointed by the quality of the page (where it still worked).