Robots that can smile in synchrony with people, and what ends up in the letters section First on this week’s show, a robot that can predict your smile. Hod Lipson, a roboticist and professor at Columbia University, joins host Sarah Crespi to discuss how mirrors can help robots learn to make facial expressions and eventually improve robot nonverbal communication.   Next, we have Margaret Handley, a professor in the department of epidemiology and biostatistics and medicine at the University of California San Francisco. She shares a letter she wrote to Science about how her past, her family, and a rare instrument relate to her current career focus on public health and homelessness. Letters Editor Jennifer Sills also weighs in with the kinds of letters people write into the magazine. Other Past as Prologue letters: A new frontier for mi familia by Raven Delfina Otero-Symphony A uranium miner’s daughter by Tanya J. Gallegos Embracing questions after my father’s murder by Jacquelyn J. Cragg A family’s pride in educated daughters by Qura Tul Ain One person’s trash: Another’s treasured education by Xiangkun Elvis Cao   This week’s episode was produced with help from Podigy.   About the Science Podcast   Authors: Sarah Crespi; Jennifer Sills   Episode page: https://www.science.org/doi/10.1126/science.zy9w2u0   About the Science Podcast: https://www.science.org/content/page/about-science-podcast Learn more about your ad choices. Visit megaphone.fm/adchoices