Pope Pius XII, painted by Peter McIntyre, 1944 (Archives New Zealand: AAAC 898 Box 128/ NCWA 202) 85 Years Ago—Apr. 13, 1941: USSR and Japan sign a five-year nonaggression pact. On Easter, Pope Pius XII cancels usual service in St. Peter’s Square due to the war and says mass in a private chapel instead. Astronomer Annie Jump Cannon dies in Cambridge, MA, age 77; she devised the Harvard Classification Scheme for stars, still used today, and classified 350,000 stars in her career. Astronomer Annie Jump Cannon (Smithsonian Institution SIA Acc. 90-105)The post Today in World War II History—April 13, 1941 first appeared on Sarah Sundin.