Bill Ingalls / NASA via Getty Images

How Did This Astronaut Grow 2 Inches After Traveling To Space?

Scott Kelly just returned to Earth after spending 340 days among the stars.

On Tuesday, March 1, NASA's Scott Kelly, accompanied by Russia's Mikhail Kornienko, touched down in Kazakhstan after spending a whopping 340 days on the International Space Station. This trip, known as Expedition 46, makes Scott the first American astronaut to spent one year in outer space.

NASA via Getty Images

Here's a selfie Scott took during a spacewalk last December. Surprisingly, it's not the first space selfie.

While aboard the station, the crew participated in research about how human bodies adjust to weightlessness and long-term spaceflight. NASA Administrator Charles Bolden said in a press release that this data will help us "take one giant leap toward putting boots on Mars."

The cool thing about this research is that Scott is an identical twin, and his brother, Mark, is a former NASA astronaut. (Talk about #SiblingGoals!) Since they pretty much share the same genes, scientists can compare Scott to Mark to figure out what genetic and bodily changes were caused by one continuous year of space travel.

The most noticeable change is that Scott experienced a two-inch growth spurt thanks to his intergalactic adventure, while Mark remained the same height. NBC News reports that astronauts' spines lengthen in space because gravity isn't around to compress the disks in their spinal column. Basically, the spinal column gets longer and taller because gravity doesn't drag it down.

"Probably almost half the time I've been here — between sleeping and working on the computer, I've spent in a box the size of a phone booth," Scott told NBC News from space.

Yep, Scott still did interviews from wayyyy up there in the galaxies. He even updated his Tumblr and tweeted breathtaking pictures. It's insane, right? Social media truly has no limits.