Earthshine

Saylor single-handedly saved the world from a devastating solar flare...and it nearly killed her. Now her father's Alliance Military Guard must track down pirated tech, missing ships, and a rogue billionaire, and they've requested a reluctant Saylor's help.
 
Tucker spent a year training the rookie Guardsmen. They call themselves Dragons. He calls them defiant. Dispatched across the ocean on a mission to retrieve Alliance's bootlegged tech, he rallies Saylor to overcome her fears and return to the field by his side.
 
Working together wielding unprecedented tech and determined to defy their destinies, the two wrangle missing ghosts, brunt force betrayal, and the swagger of power. What lies beneath the earth just might save it.