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On August 20, 1977, NASA launched the Voyager 2 probe, which in the following years flew past Jupiter, Saturn, Uranus and Neptune, making it the only spacecraft in history to visit all four outer planets. In 2018 it crossed the boundary of the solar system and continues transmitting data from interstellar space.

On August 20, 1000, Pope Sylvester II crowned Stephen I as the first King of Hungary, officially founding the kingdom and binding the country to the Western Christian world. Stephen, later canonised as a saint, transformed the ancient Magyar territory into a European feudal state, and his crown became the symbol of the Hungarian nation for a thousand years.

On August 20, 1991, Estonia declared the restoration of its independence as the coup against Gorbachev in Moscow was collapsing. Along with Latvia and Lithuania, Estonia had been illegally occupied by the Soviet Union since 1940. Its independence was internationally recognised within days, and in 2004 it joined both NATO and the European Union.