Each of the symbols has a meaning relevant to the incident it represents. Trinity was the site of the first explosion, and is therefore represented by an alpha, which is the first character of the Greek alphabet. The bombing of Nagasaki was an act of war, and Mars is the Roman god of war. The test in Siberia (actually in the Kazakh Soviet Socialist Republic) was an example of another superpower attempting to establish balance in the nuclear arms race, and the zodiacal sign of Libra is represented by the scales, making a reference to restoring the balance. The Eniwetok Atoll test took place in the middle of the ocean; hence it is symbolized by Neptune, the Roman god of the sea. The Nevada test is underground, and thus represented by Pluto, god of the underworld. The fictional incident in London was chronologically the latest to take place, and omega is the last letter of the Greek alphabet. The symbols also appear at the corresponding locations in "The Illustrated Story of the Atom Bomb" comic, which was included with the game. The fictional Low Earth Orbit (Mercury) detonation is very likely a reference to the space interceptor subproject of the Strategic Defense Initiative, nicknamed "Star Wars", contemporary with the game's development. "Trinity" also includes numerous references to British children's literature, including the Alice books of Lewis Carroll, the Mary Poppins books of P.L. Travers, and especially J.M. Barrie's novel "The Little White Bird".