The points of issue
Del Rey (Ballantine) hardcover with a Del Rey-style 'First Edition' statement and number line ending in 1 on the copyright page. ISBN 0-345-46061-8.
Is this the true first?
US Del Rey/Ballantine hardcover is the true first.
Telling it from reprints & book-club editions
A later Del Rey trade paperback (ISBN 0-345-46865-1) is a separate, subsequent issue, not the first.
Frequently asked questions
Is my copy of The Zenith Angle a first edition?
Look for these first-edition points: Del Rey (Ballantine) hardcover with a Del Rey-style 'First Edition' statement and number line ending in 1 on the copyright page. ISBN 0-345-46061-8.
How do I tell the first printing from a later one?
Check the copyright page for the publisher's first-printing convention and confirm the points above. US Del Rey/Ballantine hardcover is the true first.
Is the book-club edition the same as the first?
A later Del Rey trade paperback (ISBN 0-345-46865-1) is a separate, subsequent issue, not the first.
I have a first edition of The Zenith Angle — what should I do?
If you're clearing books, New Mexico Literacy Project offers free pickup in Albuquerque, any condition, and makes sure collectible copies aren't lost. To sell, see the author's collecting guide. Either way, nothing valuable ends up in a landfill.