PrOP-M

PrOP-M

Rendering of the PrOP-M
Mission type	Mars rover
Operator	Soviet Space Program
Spacecraft properties
Manufacturer	Mobile Vehicle Engineering Institute
Start of mission
Launch date	1971

PrOP-M (Russian: Прибор оценки проходимости — Марс (ПрОП-М), Passability Estimating Vehicle for Mars or Device Evaluation Terrain—Mars^[1]) were two Soviet Mars rovers that were launched on the unsuccessful Mars 2 and Mars 3 missions in 1971. PrOP-M were the first rovers to be launched to Mars, 26 years before the first successful rover mission of NASA's Sojourner in 1997. Because the Mars 2 and Mars 3 missions failed, the existence of the rovers was kept secret for nearly 20 years.

The rovers were built by a team led by Alexander Kemurdzhian; they were small, rectangular devices that were tethered to the lander and used skis for movement.