Call of the sun child

"Sempra has lived all of her sixteen years in an enclosed dome called the Circadia Stable Living Facility. It is structured, sustainable, and windowless. After the sun grew in intensity, causing society to become nocturnal, it was the only safe place to go. No one remembers the outside world. For 150 years the government has warned them about the deadly sun, and savage, vengeful outsiders. There is only one punishment for any crime: to be exiled from the facility. But Sempra is curious. Beyond those walls, what is there to see? When she and her childhood friend, Alden, discover a forbidden book, she begins to question the facility, and, with it, everything she has ever known"--Page 4 of cover.