Dragon Sun by Michael Ely

Years after the war that threatened the last remnants of humanity, the divided colonists of the planet Chiron become immersed in new crises as the secrets of their world begin to emerge....

Beneath the surface of the planet, a growing rebellion threatens Sheng-ji Yang's dreams of immortality, as the former executive officer of the Unity finds his carefully controlled world unraveling. Across the ocean, Lady Deirdre Skye's very life is in jeopardy as the Planetary Council withholds vital supplies, demanding that she turn over her research concerning the mysterious life force that is awakening on Chiron.

Though an ocean apart, Yang and Skye seek an alliance to overcome the forces arrayed against them. The stakes are high: power, survival, and the future of human life on Chiron. And in the end, only one of them will survive Yang's "Dragon Sun".