It usually isn’t a good sign when science-fiction authors return with sequels to their greatest hits years after the fact. Isaac Asimov’s return to his Foundation and Robot books in the 1980s are perhaps the most depressing example, but there are also more recent disappointments, like Dan Simmons’ Endymion, the sequel to his classic Hyperion. So it’s not hard to be wary of Vernor Vinge’s Children Of The Sky, a brand-new direct sequel to his 1993 masterpiece A Fire Upon The Deep. Happily, Vinge avoids major problems, making Children Of The Sky less of a Phantom Menace and more of a Star Trek: The Next Generation.
