This is a Soviet New Year postcard published in 1961 by the publishing house “Soviet Artist” Moscow (изд-ва “советский художник” Москва). The artists are V. Arbekov and G. Renkov who also designed other Soviet New Year cards.
New Year postcards were popular in the Soviet Union, and space was a popular theme. С новым годом! means Happy New Year in Russian. This design uses the crescent moon as the letter “С” and the little cosmonaut’s rocket as the exclamation point “!” of the greeting.
This postcard has a handwritten message on the back that appears to be in Finnish and sent from Petroskoi.