One of Scott Kelly's final photos from #YearInSpace might be one of his best

After 340 days aboard the International Space Station, just shy of a full year orbiting our planet, NASA astronaut Scott Kelly is finally ready to come home. Kelly, who made history as the longest American to continuously live in space, is set to make his return back to the blue planet on Tuesday.

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In one of the last photos posted by the astronaut on social media, Kelly tweeted a photo on Sunday with the words "#Countdown 2 days & a wake-up! Getting closer to Earth & hope Mars too."

Using the hashtag "#EarthArt," Kelly shared striking images time and again this year to showcase our planet's beauty in views all over the globe as seen from the International Space Station.

He witnessed historic blizzards that dumped feet of snow across the country, cool frozen lakes and impressive desert dunes, and even shared a #SpaceWalkSelfie or two.

Not to mention, the ISS got a little more colorful in part thanks to Kelly when the first flower ever grown in space made it's Instagram debut. He even came up with a brand new sport while he was there -- liquid ping pong!

Take a look back at Scott Kelly's historic #YearInSpace from the beginning by clicking through the gallery below.

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