In leading an expedition through the many-layered Jovian atmosphere in the hydrogen balloon craft Kon-Tiki, Captain Howard Falcon discovers a world where bioluminescent air plankton produce brilliant atmospheric sea-fire, predatory manta-ray creatures dominate the skies, and enormous jellyfish-like beings grow to be over a mile across.

The title story of this fourth collection from one of the genre's most celebrated authors ends with a twist—that leaves the reader questioning what it means to be human. This collection contains some of the author's most acclaimed short fiction, including "Cosmic Casanova" and "Sleeping Beauty"—stories that delight, surprise, and lead readers to ask big questions about humanity's role in the cosmos.