Astronaut Scott Kelly's Big First Day Back on Earth

The astronaut is traveling to Houston where he'll reunite with family.

— -- After making the journey from space back to Earth, astronaut Scott Kelly is spending his first full day on the planet flying halfway around the world heading to Houston, where he'll be reunited with his family.

The tests conducted include a vision check, since a micro-gravity environment can put pressure on an astronaut's optic nerves. NASA will also look at Kelly's physical health, including his bone density, muscles and cardiovascular system. He'll also be asked to complete tasks testing his motor skills and assessing his psychological state.

The one-year mission was designed to help NASA better understand what happens to an astronaut's physical and mental health during a prolonged stay in a micro-gravity environment. Kelly's results will be compared with those of his identical twin brother, Mark Kelly, who served as the control subject on Earth.

After Kelly's initial testing is complete, he told reporters last week the one thing he wanted to do most back on Earth.

"I'm going to go home and jump in my pool," he said.