 -- Astronaut Scott Kelly is poised to break the record for time in space for a U.S. Astronaut when he launches to the International Space Station today.

That’s a year with no hot showers, cold beers or the touch of his family. Kelly’s girlfriend Amiko Kauderer said she can’t call him, but he can call her, so will keep her cell phone close. It will be tough, but she said the reunion when he comes back will be special.

"For me it’s like the most romantic long-distance relationship ever," Kauderer said.

There are some amenities on the space station -- the views are out of this world, zero gravity gymnastics, and being an astronaut is still an elite job. Kelly knows that duty on the space station can mean fixing the toilet one week and being out on a spacewalk the next week.

Scott, 51, and his twin brother, retired astronaut Mark, will both be human guinea pigs. NASA will be comparing what happens to Scott’s body and brain to those of his brother Mark, while Mark is on the ground.

Mark said this will double what we know about spaceflight and the human body. "Maybe there is a little cliff out there that you fall off with regards to the radiation, bone mass, bone density, those type of things, so, I am all in," Mark said.

Scott admits it will be a tough year -- and he should know. He has pulled one six-month stint on the space station already. After "about four months, you start thinking, you know, there is a lot of stuff I miss on Earth. I feel like I have accomplished everything I need to, and I am sorta ready to go home.”

On a year-long mission, the intense yearning to go home could come later, he said, noting he hopes that yearning comes about "two-thirds of the way into the mission."

"I am kinda hoping it occurs then," Scott said.

Flight surgeon Dr. Stevan Gilmore is overseeing the research for this year in space. He knows how tough zero gravity is on the human body, and what NASA needs to know before they send humans off on a three-year round trip mission to Mars. This, he said, is an important step.

“We want to understand, is there anything that pops up between the six- and twelve-month duration so that we know if there are any large barriers out there for new missions," Gilmore said.

NASA really wants this to lead to a Mars mission. That’s why Mark Kelly agreed to the research.

"We need to figure out how people are going to live in space for really long periods of time, especially if we want to send somebody to Mars. We want to one day build a base on the Moon. Our experience with long-duration flight is six months," Mark said.

Despite all the possible dangerous side effects, the twins said they believe they are blazing a path that will take humans into space. Mark admits he has the easy job saying on earth, but noted that without taking risks, "we don’t go anywhere, we don’t learn anything, we don’t get better at anything. So, risk-taking has always been a part of the space program and always will, but in this case there is extra risk.”

What will Scott miss when he is in space for a year? All the holidays, his children’s birthdays, and good food, he said.

“The menu of food [in space] is not as large a variety as you would like, even though the weather inside the space station is generally perfect, you miss the rain, the breeze, the change of seasons," Scott said.