The stars may have finally aligned for the world's only space sibling team.
Astronaut Scott Kelly is circling the planet, fresh into a 5½-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 — texting and joking with his brother right until launch — and arrived at the orbiting complex Saturday 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. It's currently slated to be NASA's last shuttle flight.