ISS year long mission

The Year Long Mission on the International Space Station is a scientific research project that studies the health effects of long term spaceflight.Scott Kelly and Mikhail Korniyenko spent 342 days in space, with scientists performing medical experiments. Kelly and Kornienko launched on 27 March 2015 on Soyuz TMA-16M along with Gennady Padalka. The mission encompassed Expeditions 43, 44, 45 and 46. The pair safely landed in Kazakhstan on March 2, 2016, returning aboard Soyuz TMA-18M with Sergey Volkov. The mission supported the NASA Twins study, which helps shed light on the health effects of long duration spaceflight, which is of interest for Mars missions especially.

In November 2012, NASA, the Russian Federal Space Agency (Roscosmos), and their international partners selected two veteran spacefarers for a one-year mission aboard the International Space Station in 2015. The mission included collecting scientific data important to future human exploration of the Solar System. Kelly and Korniyenko already had a connection; Kelly was a backup crew member for the station's Expedition 23/24 crews, where Korniyenko served as a flight engineer.

The goal aboard the orbiting laboratory was to understand better how the human body reacts and adapts to the harsh environment of space. Data from the 12 months was intended to help inform current assessments of crew performance and health and determine better and validate countermeasures to reduce the risks associated with future exploration as NASA plans for missions around the Moon, asteroids and ultimately Mars.

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