Staff Sgt. Erik Perthel, 28th Medical Operations Squadron public health technician, stands in front of the Martin Luther King, Jr. Day of Observance poster at Ellsworth Air Force Base, S.D., Jan. 12, 2016. Perthel spoke on the importance of MLK Jr. Day of Observance and diversity during a recognition event. (U.S. Air Force photo by Airman Sadie Colbert/Released)