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Scott Kelly returns to Earth after year in space

Image: Scott Kelly
NASA astronaut Scott Kelly flashes thumbs-up signs after his return to Earth. (Credit: NASA)

Capping off a year in space, NASA astronaut Scott Kelly breathed earthly air for the first time in 340 days today after a successful, safe trip from the International Space Station to the steppes of Kazakhstan.

Since last March’s blastoff from the Baikonur Cosmodrome in Kazakhstan, the 52-year-old Kelly circled the planet more than 5,440 times, saw more than 10,800 orbital sunrises and sunsets, and put almost 144 million miles on his cosmic odometer.

The mission set a U.S. record for continuous spaceflight and blazed a trail for much longer trips to Mars and back. But to get a true sense of how long Kelly has been in space, consider this: The last time he was on Earth, Jeb Bush was the front-runner for the GOP presidential nomination.

Get the full story on GeekWire.

By Alan Boyle

Mastermind of Cosmic Log, contributor to GeekWire and Universe Today, author of "The Case for Pluto: How a Little Planet Made a Big Difference," past president of the Council for the Advancement of Science Writing.

One reply on “Scott Kelly returns to Earth after year in space”

We have a near-unicorn here, a Post space science story that gets everything right. Just one sort-of error and one thing that might be misleading:

1. The sort-of error: “He had flown over Kazakhstan — like everywhere else on Earth — 5,440 times”
Because the ISS orbit is inclined from the equator, with an orbital period of 90 minutes, it would only pass over the same point every 16 orbits (if it were exactly 90). But actually it’s much less often because the orbital period is 92.69 minutes, so ISS “loses” a bit over half an orbit a day relative to the ground; the passover point on a line of latitude creeps west at about 12 degrees per orbit. Allowing for a little windage, therefore, only about every 30th orbit would have passed somewhere roughly overhead of the landing site. So he hadn’t actually flown over that part of Khazakstan 5440 times, but probably something closer to 182 — about the same number he’d flown over every point between 51 N and 51 S.

2) the misleading for some people one: “The Soyuz plunged faster and faster towards Earth. By the time it reached the atmosphere, it had reached a speed of 17,500 miles per hour” makes it sound as if Soyuz were dropping from a tall tower. But its orbital velocity relative to the ground, starting out from ISS, was already 17,100 mph; it’s going a little faster, yes, but what it’s actually doing is mostly changing direction. That’s how spacecraft in general come down; contrary to what you see in the occasional really dumb movie, they don’t hit the brakes and drop, they just reorient from being pointed above the atmosphere to being pointed into it.

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