Expedition 43: A year in space (and on Earth)

Three astronauts departed Earth for the International Space Station (ISS) today, and two of them are in for the long haul. While most missions to the ISS last six months, American Scott Kelly and Russian cosmonaut Mikhail Kornienko will be staying on the station for a full year, primarily to see how the human body reacts to living in space for extended duration of time.

This isn’t the longest anyone’s been in space, however. That record goes to cosmonaut Valeri Polyakov, who spent 14 months on the Mir space station starting in 1994. But this mission to the ISS will be more focused on the effects on human physiology, in hopes that that information will help us design manned missions into deeper space in the future. For example, a one-way trip to Mars currently takes nine months, so we need to know what medical concerns might come up as the result of astronauts living with recirculated air, packaged food and microgravity for extended periods of time.

Microgravity and astronaut health

Astronauts health is routinely monitored in the ISS, and after they return to Earth. The most common changes noted in residents of the ISS are changes in bone density, due to weightlessness, and shifts in visual acuity. These will be monitored along side sleep patterns and changes in the astronauts microbiomes, thanks to growing understanding of their role in human health, even for those of us still on Earth.

To make this study all the richer, NASA took advantage of a unique opportunity presented by astronaut Scott Kelly and his identical twin, former astronaut Mark Kelly. While imperfect, this amazing scenario (seriously, twin astronauts?!) offers the best experimental control possible with human subjects. Since the brothers DNA and presumably physiology is a match, doctors can use Mark as a baseline on Earth to compare changes experienced by Scott while he’s in space.

Source: Year in Space Starts for One American and One Russian, NASA News