Scientists have known since the Mariner 9 mission in 1972 that volcanic features cover large portions of the Martian surface.

Later Mariner missions would reveal more of Mars's interesting geology.

Pedestal craters were first observed during the Mariner 9 mission in 1972.

The triple point pressure of water was used during the Mariner 9 mission to Mars as a reference point to define "sea level".

The findings from the Mariner 9 missions underpinned the later Viking program.

Pedestal craters were first observed during the Mariner missions.

A Hadamard code was used during the 1971 Mariner 9 mission to correct for picture transmission errors.

The total cost of the Mariner 4 mission is estimated at $83.2 million.

The Mariner 10 mission (1974) mapped about half the surface of Mercury.

Valles Marineris was discovered by and named for the Mariner 9 mission.