Richard Powers’ last novel, “The Overstory,” was a 600-page deep-dive into the science of forests, and the relationships between trees and human beings. His newest, “Bewilderment,” is less than half that length, but both more vast and more intimate in scope. It is the story of an astrobiologist who looks for life on other planets, while he navigates a complex relationship with his young son. Powers joins us in front of an audience at Parkrose High School.