Mission Twinpossible

by Jeffrey Kluger,

The Kelly twins–one in orbit and one on Earth–may help NASA unlock the secret of long-term space travel.

When Scott Kelly calls home from the International Space Station (ISS) sometime next year, whoever answers the phone may simply hang up on him. The calls will be welcome, but the link can be lousy, with long, hissing silences breaking up the conversation. That’s what happens when you’re placing your call from at least 229 mi. (369 km) above the Earth while zipping along at 17,500 m.p.h. (28,164 kph) and your signal has to get bounced from satellites to ground antennas to relay stations like an around-the-horn triple play. “When someone answers, I have to say, ‘It’s the space station! Don’t hang up!’” says Kelly.
2015 The Year Ahead Scott Kelly Time Magazine CoverPhotograph by Marco Grob for Time

That’s not likely to be necessary when he calls his brother Mark. Perhaps best known as the husband of former Congresswoman Gabrielle Giffords, who was grievously wounded in an assassination attempt in 2011, Mark is a former astronaut who has been to space four times.

The brothers’ connection will be more important than ever beginning in March, when Scott takes off for a one-year stay aboard the space station, setting a single-mission record for a U.S. astronaut.

A year in space will require Scott to leave behind a lot: his Houston home, his daughters—Samantha, 20, and Charlotte, 11—and his girlfriend of five years, Amiko Kauderer, a NASA public-affairs officer. (He and his first wife are divorced.) But he won’t, in some ways, leave Mark behind.

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