Learn more by clicking the Google or Facebook button below. Population Demographics for Tonasket, Washington in 2016 and 2017. Other Counties and Cities in Washington.
Sidereal Period versus Synodic Period. 1  Measuring the motion of the Moon around the Earth relative to the distant stars leads us to what is called the sidereal period. 2  Measuring the motion of the Moon around the Earth relative to the Sun leads us to what is called the synodic (pronounced si-nod-ik) period.
The time it takes the Earth to rotate once is called a sidereal day. The actual rotation time is about 23 hours and 56 minutes.The mean solar day is longer, exactly 24 h â¦ ours, because of the distance the Earth moves in its orbit around the Sun.This orbital motion causes the small daily apparent motion of the Sun to the East in the sky.he time it takes the Earth to rotate once is called a sidereal day. The actual rotation time is about 23 hours and 56 minutes.