There are no light sabers, telepathy or warp drives here. No hyperspace or jump points, either, just the hardest science we know to show how interstellar war might really take place.

The aliens on Titan are building a gigantic 200-kilometer railgun to launch devastating projectiles at Earth. Each mass-produced meteor will hit with the kinetic force of a nuclear bomb, destroying one targeted factory at a time.

Humanity must destroy that railgun.

The problem: any decision will take years to implement. A wrong choice now can mean bitter defeat later in the ultimate Darwinian game of 4-D chess.

Earth begins assembling 100,000-ton Orion ships, vessels that use nuclear bombs for propulsion. How many are needed to win at Saturn? The journey will take one year. Time is ticking on the decision.

As an afterthought, four stealth ships are launched. They will take three years to reach Saturn. Surely, the war will be over by then.

Nothing could be further from the truth.

SATURN PROTOCOL is the second book in the GRAVITY WARS series, written by bestselling author Vaughn Heppner.