Original Title:

Moon phases

Keywords:

Moon Moon phases astronomy Solar System rotation movement translation movement

Description:

Since ancient time the moon has been a subject of study. The various shapes of the Moon shows in the sky came to known as the Moon phases. Due to its position relatively to the Earth, the phases change from New Moon (when no Moon is visible), to Waxing Crescent, to First Quarter, to Full Moon (when the entire face of the Moon is visible). Galileo Galilei was the first person to turn the telescope towards the Moon and immediately realised the wonderful three-dimensional details of its surface - the valleys and peaks, the areas with shadows and the illuminated areas. Galileo studied how the light hit the Moon and the way the shadows moved across the surface unevenly at the line where the lighted half of the Moon met the dark half. No, the Moon was not smooth or perfectly round!