Impact
(Book)

After a meteorite passes straight through the earth, Wyman Ford is called on to investigate the exit hole. What he discovers shatters all that is known about the universe. His investigation leads him to one of Mars' moons where a structure in the shape of a gun is found. It had been built to destroy any intelligent life that might challenge it, but who built it? Since it obviously poses a threat to Earth, Ford's team races against time to dismantle it.

CIA agent Wyman Ford is sent to Cambodia to locate the source of some radioactive gemstones--a mission that has links to a young woman's search for a meteorite she saw streak through the sky in Maine, and the murder of a researcher at the National Propulsion Facility who discovered gamma rays originating from Mars.