Death’s End by Liu Cixin
The novel “Death’s End” by Liu Cixin was published for the first time in 2010. It was translated into English by Ken Liu. It’s the third book of the trilogy known as The Three-Body Problem or Remembrance of Earth’s Past and follows “The Dark Forest”.
Cheng Xin is a part of the team working on the Staircase Project which aims to send a probe toward the Trisolaran Fleet. The examination of the technical limitations shows that it’s impossible to use it to send a human being, and director Thomas Wade decides to send only a person’s brain. Yun Tianming chose euthanasia because of an incurable disease but agrees to participate in the Staircase Project. The launch seems unsuccessful but Cheng Xin received a star as a gift from Yun, who was in love with her.
After a period of hibernation, Cheng Xin awakens in the deterrence era in which the Earth and Trisolaris maintain a fragile truce based on mutual threats to reveal the coordinates of their respective planets to the entire universe. Cheng Li is appointed to be the Swordholder, the human representative who is tasked with transmitting the coordinates of Trisolaris but when the Trisolarans attack, she decides not to activate the device.