On March 27th, an American astronaut named Scott Kelly blasted off from Earth and, six hours later, clambered onto the International Space Station. He’s been there ever since. Each day, the I.S.S. orbits the planet fifteen and a half times, which means that after a month Kelly had completed more than four hundred and fifty circuits. By now, he’s made nearly a thousand.
Kelly, who is fifty-one, is short—five feet seven—and stocky, with a round face and a thin smile. If all goes well, he will not return to sea level until March, 2016. At that point, he will have set an endurance record for an American in space.
Even in brief bursts, space is tough on the human body. Changes in intracranial pressure can lead to eye problems. Weightlessness induces vertigo. Fluids collect in places they shouldn’t. Muscles atrophy and bones grow brittle. Astronauts’ internal organs drift upward and their spines extend. It is expected that by the time Kelly finally descends he will have stretched to five feet nine.
NASA has dubbed Kelly’s circular odyssey the One-Year Mission. As he spins around the Earth, scientists at the agency are tracking his physical and emotional deterioration, monitoring, among other things, his sleep patterns, his heart rate, his immune response, his fine motor skills, his metabolism, and his gut bacteria. Kelly has an identical twin, Mark, who was also an astronaut. (Mark Kelly is perhaps best known as the husband of Gabrielle Giffords, the former Arizona congresswoman.) In the course of the year, Mark will submit to many of the same cognitive and physiological tests as Scott, though without leaving Earth. This will provide a glimpse into the effects of space travel down to the molecular level.
Kelly’s One-Year Mission represents a kind of dress rehearsal for a longer, straighter, and even more punishing voyage. In NASA’s Buzz Lightyear-esque formulation, it’s “a stepping stone” to “Mars and beyond.” At its closest, Mars is thirty-five million miles from Earth, and, under the most plausible scenario, getting there takes nine months. Owing to the relative motion of the planets, any astronauts who make it to Mars will have to cool their heels on the red planet for three more months before rocketing back home. What NASA learns about Kelly—at least, so the theory goes—will help it anticipate and overcome the challenges of interplanetary travel.To read more, click here.