4MV

The 4MV planetary probe (short for 4th-generation Mars-Venus probe) is a designation for a common design used for Soviet unmanned probes to Mars and Venus.

It was an incremental improvement of earlier 3MV probes and was used for Mars missions 2 to 7 and Venera missions 9 to 16. Different versions of the bus exist, for example 4V-1, 4V-M and 4V-2. The same base design was also used for earth-orbiting space observatories.