It seems that Russian scientists are still looking for non-conventional solutions to create propulsion which could be used in future mission to Mars.
Sometimes it is hard to threat seriously ideas from Russia, especially these which are referring to nuclear power. Recent conceptions of using modified ICBM with nuclear warheads to destroying asteroids or changing their trajectory were actually more science fiction than reasonable solution for real problems. Now, according to Tass, chief of Rosatom State Atomic Energy Corporation, Sergey Kiriyenko, announced on March 2, 2016, that Rosatom is ready for starting project of nuclear propulsion for space mission purposes. Statement was not given during interview but was placed in official speech given by Kiriyenko in Federation Council, Russian upper house of parliament. Sergey Kiriyenko claimed that such propulsion will reduce time needed for reaching Mars orbit from one year to 1-2 months comparing to ordinary chemical rocket propulsion. Nuclear propulsion would also give possibility for performing maneuvers and accelerating during flight. There were not unveiled any details of the construction, but probably this propulsion will be based on nuclear fission, where nuclear energy is used for heating hydrogen propellant (similar to US Air Force Space Nuclear Thermal Propulsion (SNTP) project developed in the end of the eighties). Tass claims that work under space nuclear propulsion was started in 2010 with first technical projects in 2012. It was scheduled to start trials in 2015, but still it there was not any kind of prototype unveiled. Project total investments were planned for $580 million until 2019. In 2018 it is planned to start flight tests of the propulsion stated Sergey Kiriyenko.
Russia has experience with nuclear reactors in space. During seventies and eighties Soviet Union created and manufactured series of 32 radar reconnaissance satellites for tracking NATO submarines. They were called RORSAT (US-A in USSR) and were launched on atop of Tsiklon-2 rockets from Baikonur cosmodrome. Unfortunately, Russia is also experienced with multiple nuclear disasters with RORSAT satellites. On April 25, 1973, RORSAT and Tsiklon-2 failed to reach orbit and satellite fell into Pacific Ocean near Japan with all Uranium-235 nuclear fuel onboard. On January 24, 1978, RORSAT codename Kosmos-954, failed to jettisoned nuclear core before reentry. It fell to northern part of Canada and contaminated 124 000 square kilometers. In 1982 RORSAT Kosmos-1402 failed to jettisoned nuclear fuel and fell into Atlantic Ocean with part of nuclear core.
On picture above: NASA vision of nuclear propulsion in Mars vehicle.