Soviet space exploration history has been well documented on Soviet stamps. These Soviet stamps cover a broad spectrum of subjects related to the Soviet space program. While much of the focus has been placed on the nation's notable "firsts" in space flight, including: Earth orbiting satellite, Sputnik 1; animal in space, the dog Laika on Sputnik 2; human in space and Earth orbit, Yuri Gagarin on Vostok 1; first spacewalk, Alexei Leonov on Voskhod 2; woman in space, Valentina Tereshkova on Vostok 6; Moon impact, 1959, and uncrewed landing; space station; and interplanetary probe; numerous stamps have paid tribute to more general astronomical topics as well.[1] [2]
. Sowjetunion-Spezial-Katalog 2005/06. Michel. Michel catalog. 2006. Schwaneberger Verlag . 14 September 2010.
. 2011 Scott Standard Postage Stamp Catalogue. Scott. Scott catalogue. 5. 2010. Amos Advantage. 14 September 2010.