Twins to be first blood relatives together in space

CAPE CANAVERAL, Fla. - The stars may have finally aligned for the world's only space sibling team.

Astronaut Scott Kelly is circling the planet, fresh into a 5 1/2-month space station mission. His identical twin, Mark, will join him next year, if NASA's shuttle schedule holds up.

Together, they will become the first blood relatives to meet up in space.

"It's something we hoped would happen," Mark said. "It wasn't done by design. But we're fortunate. I think it will be fun for us." Scott is the International Space Station's next commander. He took off aboard a Russian Soyuz rocket early Friday and arrived at the orbiting complex last night.

Mark is space shuttle Endeavour's next commander. He's due to take off at the end of February and knock on the space station door March 1.

Don't expect any handshakes when the Kellys unite more than 200 miles up. The 46-year-old brothers - Navy captains and former fighter pilots - have never shaken each other's hands and don't plan to start just because the space station cameras are rolling.

Rather, count on embraces and arm-wrestling when the hatches pop open between the space station and Endeavour.

The Kellys promise no gags or matching outfits in space. They insist they've never done any of that.

So how will they mark the historic occasion? The Associated Press posed the question in a recent interview.

"We're going to arm-wrestle," Mark replied.

"I was going to say the same exact thing," Scott said.

They laughed, then speculated on which twin would win, and whether it might end up a draw, with the two rotating around each other in weightlessness.

"I'll win because I'll have more zero-g experience," Scott said.

"By that point, your bones will be like powder. Your muscles will be atrophied," Mark countered.