I was hoping to have liked this more, however, I liked it enough that I will read the second one. Even for a young adult book I felt it was a little simplistic and borrowed too heavily from others. The book also lacked quite a bit of detail. All we get about the main aliens is that they have slightly translucent blue skin and have two heads. Not really much to go on there. Others are described as being wrinkly or dusty or big and yellow. There is very little description given about this amazing, fantastic place these kids end up in. What do the buildings look like? What do the "cars" look like? Can you see the other rings? How are the rings oriented to each other? Is there some distortion in the "sky" where this wormhole in the center of the rings is supposed to be? Perhaps more gets fleshed out in the other books.

Also, some editor at some point should have caught the incorrect usage of "light-years".