MARPOST (2000–2005) (jan 1, 2000 – mar 1, 2000)
“Mars Piloted Orbital Station” Is a Russian proposed manned orbital mission to Mars, using a nuclear reactor to run an electric rocket engine.
(The draft project for MARPOST was confirmed as of 2005. Design for the ship was proposed to be ready in 2012, and the ship itself in 2021.)
Added to timeline:
Timeline of Mars