What are the Northern lights? Why do they appear? Where can you see them? The answers are all in this book. The Northern Lights is a book-banded reading book for developing readers, carefully levelled at Purple Book Band for guided reading. Illustrated throughout with beautiful photographs, this 432-word non-fiction book features a more demanding text with an extended vocabulary. What are the Northern lights? Why do they appear? Where can you see them? The answers are all in this book. The Northern Lights is a book-banded reading book for developing readers, carefully levelled at Purple Book Band for guided reading. Illustrated throughout with beautiful photographs, this 432-word non-fiction book is suitable for ages 7 - 8. The Northern Lights features a more demanding text with an extended vocabulary. With a wider vocabulary, the characters are more three dimensional, and illustrations are less important. It encourages more independent reading. The Northern Lights is part of Ransom Reading Stars, a structured programme for children learning to read. The series has fifteen levels: four phonics levels and eleven book band levels (Pink through to Lime).