Astronaut Scott Kelly heading back to Houston

HOUSTON (KTRK) -- Astronaut Scott Kelly is scheduled to return home to the Houston area early in the morning, after spending nearly a year in space.

He landed yesterday in Kazakhstan and is now on a plane home, which is due to land at Ellington Field around 1:50am. He will be greeted by friends, family and dignitaries including NASA administrator Charles Bolden and Dr. Jill Biden.

WATCH NASA TV LIVE: Astronaut Scott Kelly expected to return to Houston around midnight

After 340 days cooped up in the confines of the International Space Station, one of the first things Scott Kelly wanted to talk about after landing back on Earth was the weather. It's something he told us before leaving Earth that he knew he would miss.

"The cold air. Fresh air. The air. I don't mean to say it's not fresh on the station, but it's -- there's nothing like new cold air coming into the capsule," said Kelly during an interview shortly after landing.

Kelly now holds the record for the astronaut who has spent the longest amount of time in space. The mission was designed to test how the human body reacts to longer term stresses of space and weightlessness. He tells NASA it was bittersweet leaving leave the station. He missed his friends and loved ones at home.

Recently he called friend Allen Flores and left this voice mail for him saying: "Hey you shouldn't be screening your calls when it's space calling!! Hey it's Scott."

Flores keeps the voicemail as a sort of momento. He says Scott called him every week or two from space just to check in.

"Yeah that is very cool. Scott's a really humble and modest guy, asking more about our world, instead of thinking how important his mission is up there," Flores said.

Kellly's friends say they are excited to hear Scott's stories about his time in space.

"It feels like the other day for us. But for him it's been a long time, but it's great that he made it back safe," said friend Robert Tijerina.

Tijerina says it was good to see Kelly exit the capsule after landing. Kelly is being watched closely during his first 24 hour hours by a NASA flight surgeon. Experts say spending so long in microgravity can effect balance, cause vertigo and vomiting.

Former NASA flight surgeon Sam Strauss says he does not expect Kellly to have too many problems adjusting to gravity again, because of his prior flight experience and training.

Strauss says the absence of gravity actually would have made Kelly about an inch taller while on orbit because it allows the spinal ligaments to stretch. Upon his return however, he says, gravity would take over and Kelly would return to his normal pre-flight height.

Interestingly some believe Kelly now to be "younger" by about 1/100th of a second, Strauss says. Under the rules of relativity if the space station is orbiting at 7,500 miles per hour he would age more slowly than those of us on the Earth's surface.