Space exploration has become the subject of post stamps since the very beginning, that is since the Sputnik I was launched by the USSR in 1957. On the post stamps the heroes of the outer space exploration were depicted (dog Laika, Yuri Garagin, Valentina Tereshkova, Neil Armstrong), the stamps were symbolizing the following phases of the space conquest (first flight of an artificial satellite, first human flight, first landing on the Moon), as well as they were depicting the new astronautic technologies, which - especially during the cold war - was one of the propaganda fight of the USA and the USSR. Some stamps with that subject matter, created in 20th as well as 21st centuries are of futuristic nature - they "foreshadow" human's landing on Mars and expeditions to other solar systems.
