Composer Julia Wolfe lives in Lower Manhattan, just blocks from where the Twin Towers once stood. She and her family watched 9/11 unfold around them, and dealt with the aftermath. She wrote one of her most stark, concise works as a response. She called it “Compassion.” Hear the piece performed in concert by pianist Conrad Tao at the Aspen Music Festival and School -- and more of Julia's story -- in this episode of Centennial Sounds from CPR Classical and Colorado Public Radio.