NASA will televise the moment three astronauts return to Earth from the International Space Station.

The team from Expedition 45 are expected to arrive on Friday December 11 after 141 days in space.

Flight engineers Kjell Lindgren from NASA, Oleg Kononenko from the Russian Federal Space Agency (Roscosmos) and Kimiya Yui from the Japan Aerospace Exploration Agency will undock their Soyuz TMA-17M spacecraft from the space station at 4:49am (US time).

The astronauts' return will be streamed throughout the day, and into the night, culminating to video of the landing and post-landing interviews.

Dubbed "the one year mission", the astronauts were sent to the station to help research how to advance NASA's journey to Mars.

The three joined Expedition 44 crew members to bring the International Space Station total to six.

NASA astronauts Scott Kelly and Kjell Lindgren spent 7 hours and 48 minutes working outside the International Space Station on the 190th space walk in support of station assembly and maintenance on November 6, 2015. The astronauts restored the port truss (P6) ammonia cooling system to its original configuration, the main task for the spacewalk. ( Supplied: NASA )

The International Space Station is a microgravity laboratory in which an international crew of six people live and work while orbiting the Earth every 90 minutes.

The station allows experts to test new technologies and research, not able to be tested on Earth.

The space station has been continuously occupied since November 2000. In that time, more than 200 people from 15 countries have visited.

NASA Expedition 45 Commander Scott Kelly tries on his spacesuit for a fit check before a space walk. ( Supplied: NASA )

At the time of undocking on December 11, Expedition 46 will begin aboard the station under the continued command of astronaut Scott Kelly.

Kelly and Russian cosmonaut Mikhail Kornienko are spending one year in space — twice the typical mission duration — to provide researchers the opportunity to advance their knowledge of the medical, psychological and biomedical challenges faced by astronauts during long-duration spaceflight.

Along with his crewmate Sergey Volkov of Roscosmos, the three-person crew will operate the station for four days until the arrival of three new crew members in mid-December.