Main Page | See live article | Alphabetical index Diurnal motion is an astronomical term referring to the apparent daily motion of stars in "orbit" around the Earth. It is important to note that stars only appear to be orbiting the Earth. Such motion can be shown by time-exposure photography. Some of the more circumpolar stars may appear to be motionless. See also: celestial sphere positional astronomy This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.