ISS024-E-014263 (11 Sept. 2010) --- NASA astronaut Tracy Caldwell Dyson, Expedition 24 flight engineer, looks through a window in the Cupola of the International Space Station. A blue and white part of Earth and the blackness of space are visible through the windows.
Astronauts today, such as Tracy Caldwell Dyson, have the chance to gaze upon Earth from space stations, but this will not be the case for longer space voyages

Design is key to beating monotony on long trips to Mars or the Moon