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 sidereal month is the actual time it takes the Moon to orbit the Earth, but the lunar month is how long it takes for us to notice the completion of the orbit (to return to a moon phase) due to the Earth also orbiting around the Sun.