At the TCA 2019 summer press tour, Amazon announced orders for The Expanse Season 5, and Carnival Row Season 2, both ahead of their respective premieres. Season 4 of The Expanse will drop on December 13, while Carnival Row is set to debut on August 30.
Presumably, The Expanse Season 5 will center on some of the events in Book 5, titled Nemesis Games, which was written by James S.A. Corey (co-authors Ty Franck and Daniel Abraham) in 2015. Per Amazon, Season 4 “begins a new chapter for the series with the crew of the Rocinante on a mission from the U.N. to explore new worlds beyond the Ring Gate. Humanity has been given access to thousands of Earth-like planets which has created a land rush and furthered tensions between the opposing nations of Earth, Mars and the Belt. Ilus is the first of these planets, one rich with natural resources but also marked by the ruins of a long-dead alien civilization. While Earthers, Martians, and Belters maneuver to colonize Ilus and its natural resources, these early explorers don’t understand this new world and are unaware of the larger dangers that await them.”
Source: IGN.com Amazon Gives The Expanse an Early Season 5 Order