Amazon.com Product Description (ISBN 0441045340, Mass Market Paperback)

Third Ace printing, same cover as first two. This is D-534, published in 1961. 200 years after the Destruction, young Fors set off to explore the empty lands to the north. He was a member of a clan which concerned itself with recapturing the knowledge and skills of their ancestors. By adding to that knowledge, Fors hoped to secure a place as one of the leaders of his clan, a "Star Man," like his late father.