This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced

Written by a noted astronomer, this comprehensive textbook explores the various laws and theories governing the movements of the celestial bodies in the univers

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced

This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work was reproduced