Ross Montgomery started writing stories as a teenager, when he should have been doing homework. After graduating, he decided to channel these skills into teaching at a primary school.

Author of Alex, the Dog and the Unopenable Door and The Tornado Chasers, Ross has been shortlisted for the Costa Book Award and nominated for the Branford Boase Award. He lives in Brixton, London. Space Tortoise is his second picture book, following The Building Boy.

Sarah grew up in Anglesey, North Wales. She studied illustration at the University of the West of England, in Bristol, and hasn't looked back since.

Sarah has created many books, working for a large variety of publishers, including illustrating the Rumblewick series, which has sold worldwide and is under movie option with DreamWorks.

Her Princess series, written by Caryl Hart, has sold over 220,000 copies worldwide. Sarah lives in Bristol with her husband, two children and a grumpy guinea pig.