Soyuz rocket launches yearlong space station crew

BAIKONUR, Kazakhstan, March 27 (UPI) -- Two Russian cosmonauts and one American astronaut successfully departed Earth on Friday, propelled by a Soyuz rocket launched from the Baikonur Cosmodrome in Kazakhstan. They're headed for the International Space Station.

As of 4:00 p.m. EST, the rocket had achieved third-stage separation and the Soyuz TMA-16M spacecraft had entered Low Earth orbit. If all goes as planned, the craft will dock onto the space station late Friday night (early Saturday morning in Kazakhstan).

.@StationCDRKelly & crew are now in orbit. Docking w/ @Space_Station at 9:36pm ET. #YearInSpace has begun! pic.twitter.com/uBbTY4VE4N

— NASA (@NASA) March 27, 2015

Notably, the journey will see NASA astronaut Scott Kelly and Russian Cosmonaut Mikhail Kornienko remain aboard ISS for 12 months -- the longest space mission in several decades. Scientists with the U.S. and Russian space agencies will be monitoring the health effects of lengthy stints in microgravity.

NASA is especially interested in the physiological parameters of lengthier space missions as it perfects plans for a future trip to Mars.

"Long exposure to a zero-gravity environment can affect the human body in multiple ways," NASA officials wrote in press release. "Some physical symptoms can include changes to the eyes, muscle atrophy and bone loss."

Researchers are also interested in the psychological effects of a year spent in limited company. Lengthy periods of solitude have the potential to have negative impacts on the psyche.

Specifically, scientists will measure the effects of a yearlong space mission on behavior, sleep patterns, visual impairment, metabolism, immune health, stress levels and physical performance. The results of all experiments will be shared between Russian and American science teams.

Sitting between Kelly and Kornienko inside the craft is Commander Gennady Padalka, a veteran cosmonaut who will break the all-time record for time in space during his six months aboard the space station.