Octavia Gone by Jack McDevitt

After being lost in space for eleven years, Gabe finally makes his triumphant return to reunite with Alex and Chase and retrieve a possibly alien artifact--which may lead them to solve the greatest archaeological mystery of their careers, in the eighth installment of the Alex Benedict series.

After his return from space, Gabe is trying to find a new life for himself after being presumed dead--just as Alex and Chase are trying to relearn how to live and work without him. But when a seemingly alien artifact goes missing from Gabe's old collection, it grants the group a chance to dive into solving the mystery of its origins as a team, once again.

When a lead on the artifact is tied to a dead pilot's sole unrecorded trip, another clue seems to lead to one of the greatest lingering mysteries of the age: the infamous disappearance of a team of scientists aboard a space station orbiting a black hole--the Amelia Earhart of their time. With any luck, Alex, Chase, and Gabe may be on the trail of the greatest archaeological discovery of their careers...

In Octavia Gone, Nebula Award winner McDevitt, who Stephen King has called "the logical heir to Isaac Asimov and Arthur C. Clarke," has created another terrific science fiction mystery in his beloved Alex Benedict series.

This book is part of the "Alex Benedict" series.
Here are some other books from this series: