It might feel great for him to be back on Earth

But, wouldn't it have been great if NASA had asked you to take Scott Kelly's place? His recently-completed 340-day stay will help get us ready to go to Mars. Sign me up! (Preacher in Space)

To me, the most curious element of Kelly's experience was how he experienced time.

“The only big surprise was how long a year is,” Kelly said Friday, three days after returning to Earth from the longest stint anyone has ever spent on the International Space Station. “It seemed like I’d lived there forever.” Scott’s identical twin Mark, a retired astronaut who spoke often to his brother during their nearly yearlong separation, gave a blunter account. “Every time I would say to my brother, ‘A year is going by quickly,’ he would say, ‘No, it’s not,’ ” Mark Kelly said Friday.

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