The Celestial Globe The Kronos Chronicles:

Thirteen-year-old Petra Kronos, her tin spider Astrophil and their Roma friends Neel and Tomik are surprised by revelations about Dee, Kit and Petra's father as they face Prince Rodolfo of Bohemia, who will do anything to possess a powerful object, the Celestial Globe, in the follow-up to The Cabinet of Wonders.