Image sequence showing the International Space Station (ISS) crossing the Moon's disc in its waxing gibbous moon phase during twilight. This is when a moon is approaching a full moon (increasing in size) and is therefore said to be waxing. It is gibbous when it is more than half full. The ISS takes a few minutes to cross the sky, orbiting the Earth every 92 minutes. The Moon rises and sets daily due to the rotation of the Earth, taking just over 27 days to complete its orbit. Photographed from Dark Sky Alqueva Reserve, Cumeada, Reguengos, Portugal.