Tranquility module

The second-biggest chunk of NASA's $50 million Commercial Crew Development (CCDev) initiative award is an $18 million disbursement to the Space Exploration division of aerospace giant Boeing, whose history with the space agency stretches back decades.

One of the Houston-based division's most recent contributions is in the Tranquility module, to be delivered to the International Space Station by the space shuttle Endeavour, which is scheduled to take off Sunday.

For Tranquility, pictured here with the smaller Cupola module being attached, Boeing produced components such as window panes, hatches, and berthing mechanisms, and provided engineering and testing support.