I am trying to remember the name of a science fiction book I borrowed from a library in Ohio sometime between the years 2001-20092001–2009, though it was probably closer to the end of that period than the beginning. I'm going to start by saying this book is not integral trees, I say that because when I search for my book, all I can see is that one. I've never read integral trees, but I'm very certain that it is not the book I am looking for.
The book takes place inside a gas giant planet with a breathable atmosphere. This planet has a machine at it'sits center with a burning core which supplies all of the heat and light inside the clouds of the planet. If I remember correctly, the planet is either in deep space or the nearest star is dead.
He estimates it'sits size by seeing a speeder bike which seems to be going full speed, behind it is a contrail he thinks must be at least x meters long, and if the ship behind it is even larger than that...then it must be (some really big number). Obviously, the picture he's looking at is probably the cover of the book.