Crewmembers of Expeditions 14 and 15

The International Space Station is abuzz with activity this week, with the arrival of a new crew (including high-profile space traveler and former Microsoft mogul Charles Simonyi), and one astronaut training to keep pace with the Boston Marathon from more than 200 miles above the planet.

Pictured here are the crews of Expeditions 14 and 15 aboard the space station (back and front rows, respectively). Expedition 15 arrived at the space station Monday, joining the Expedition 14 crew that had been aboard since last year. The new threesome docked in their Soyuz spacecraft two days after launching from Baikonur Cosmodrome in Kazakhstan.

Simonyi (front row, right), an American who is flying under contract with the Russian Federal Space Agency, will return home with Expedition 14 on April 20. He flew aloft with Flight Engineer Oleg Kotov (left) and Commander Fyodor Yurchikhin (center).

Expedition 14 Commander Michael Lopez-Alegria (back row, left) and Flight Engineer Mikhail Tyurin (back row, center) have been living in space since September. Flight Engineer Sunita Williams (back row, right), who rode Space Shuttle Discovery to the station in December, will stay onboard and join Expedition 15.