Astronaut Scott Kelly prepares for a year in space on ISS

HOUSTON (KTRK) -- NASA astronaut Scott Kelly is about try something no American has ever done. He wants to spend one continuous year in space.

It will soon be twelve straight months without gravity for veteran astronaut Scott Kelly.

Though four Russians have already done it, Kelly will be the first American ever to spend that long in space.

The veteran astronaut tells Eyewitness News he will be 50 years old when he blasts off this coming week aboard a Russian Soyuz from Kazakhstan, 52 when he returns.

NASA is doing this as a study to see the effect on Kelly's body and his cognitive function. The lack of gravity from shorter stints already is known to cause bone loss and vision deterioration.

But with Kelly, researchers can compare to almost an exact replica of his DNA right here on earth his twin brother Mark, a former astronaut.

The whole idea Scott Kelly says is to learn more so we can plan better for that mission one day when humans go to Mars.

"Exploring is hard. It's very easy to sit at home and do nothing by doing challenging things we learn more and what learn improves life on earth," Kelly said.

Among the things Kelly says he will miss most he says is the weather and the ability to shower. The year-long mission is twice as long as Kelly's last stint on the International Space Station.

Launch is set for Friday 2:42 pm Houston time. You can view the launch live at abc13.com.