The International Space Station is growing. In the past six months alone, astronauts have unfurled 230-ft solar wings, added a 30,000-lb docking port (Harmony), installed a 28,000-lb science lab (Columbus) and, while they were at it, a European robot ship (Jules Verne) flew up to the ISS and docked itself.

A new round of flybys over North America begins in early May.