1974 in spaceflight
In 1974 Mariner 10 visited Mercury that saw a spacecraft that visited Mercury for the first and last time in the 20th century.
This is a list of spaceflights launched in 1974.
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Wikipedia
In 1974 Mariner 10 visited Mercury that saw a spacecraft that visited Mercury for the first and last time in the 20th century.
This is a list of spaceflights launched in 1974.