Fifty years after the Titan and Rhea missions humans are now established in two bases on Mars.
The base near the Tharis Mons mountain range is constantly being expanded. Full time teams of geologists, scientists, and engineers make a remarkable discovery while looking for metal ores under the surface near the base.
What they find is far beyond what they can possibly explain.
Tharsis is the third book in the Titan, Rhea, Tharsis.