On ongoing theme. Any stamp that commemorates space exploration. This does not include sci-fi related stamps.
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Letter Rate 5¢ Package Rate 5¢ Postcard Rate 4¢ Effective 1/7/1963 American President Lyndon B Johnson (11/22/1963-1/20/1969) Argentine President Juan Carlos Onganía (6/29/1966-6/8/1970) Australian Prime Minister Harold Holt (1/26/1966-12/19/1967) Austrian President Franz Jonas (6/9/1965-4/24/1974) Bahamian Premier Lynden Pindling (1/16/1967-5/10/1969) Belgian Prime Minister Paul Vanden Boeynants (3/19/1966-7/17/1968) Brazilian President Artur da Costa e Silva (3/15/1967-8/31/1969) British Prime Minister Harold Wilson (10/16/1964-6/19/1970) Canadian Prime Minister Lester B Pearson (4/22/1963-4/20/1968) East German President Walter Ulbricht (9/12/1960-8/1/1973) German President Heinrich Lübke (9/13/1959-6/30/1969) Japanese Prime Minister Eisaku Sato (11/9/1964-7/7/1972)