1421 Esperanto in the outer asteroid belt at a distance of 2.8–3.4 AU once every 5 years and 5 months (1,983 days; semi-major axis of 3.09 AU). Its orbit has an eccentricity of 0.08 and an inclination of 10° with respect to the ecliptic. The body's observation arc begins with its first observation as at Heidelberg Observatory in October 1906, almost 30 years prior to its official discovery observation at Turku. This minor planet was named by the discoverer after the artificial language, Esperanto, which was created by inventor and writer, Ludwik Lejzer Zamenhof (1859–1917), who used the pseudonym "Doktoro Esperanto". The
Ludwik Kalkstein Ludwik Kalkstein Ludwik "Hanka" Kalkstein, also known as Ludwik Kalkstein-Stoliński, (13 March 1920, Warsaw – 26 October 1994, Munich); was one of the better known German Gestapo agents during the Warsaw Uprising as well as a Stalinist informant following the Soviet takeover of Poland. Along with his wife (Blanka Kaczorowska "Sroka"), they became traitors to the Armia Krajowa under not just one but two consecutive totalitarian regimes. Kalkstein was responsible for the arrest and execution by the Nazis of at least fourteen Polish underground officers, including the General Stefan Rowecki. Arrested by the Gestapo in April 1942 and interrogated, Kalkstein