"Though unchanged from 2018, this setting should be taken not as a sign of stability but as a stark warning to leaders and citizens around the world," Rachel Bronson, The Bulletin of Atomic Scientists (BAS) president and CEO, said in a statement. The Doomsday Clock was originally conceived in 1947 by a cadre of former Manhattan Project physicists, and was meant to symbolically picture how close humans were to nuclear annihilation.