Threshold

When the strange fossil she'd discovered had ended up giving her a trip toMars, Helen Sutter thought she'd gone about as far as any paleontologist would

ever go in her lifetime. But when you've also married A.J. Baker, overconfident

super-sensor expert for the only private agency in space, the Ares Corporation,

and your best friend Madeline Fathom Buckley is a former secret agent who's just

signed on as the chief of security for the newly created and already embattled

Interplanetary Research Institute of the United Nations, there's always

somewhere farther to go. The newest discoveries will take her, A.J., and their

friends Jackie, Joe, and Madeline to the mysterious asteroid Ceres, and beyond,

in a desperate race to Jupiter's perilous miniature system of

radiation-bombarded moons. The next gold rush is on for alien technology, hidden

in lost bases around the system. And there are people willing to do anything to

get it — even plan the first interplanetary war, four hundred million

miles from home!