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.
A sidereal day is the time it takes for a planet to complete a single rotation on its axis. On the other hand, a solar day is the time it takes for the Sun to return to the same place in the sky. On Earth, a sidereal days last 23 hours 56 minutes and 4.1 seconds, whereas a solar day lasts exactly 24 hours. In Venusâ case, it takes a whopping 243.025 days for the planet to rotate once on its axis â which is the longest rotational period of any planet in the Solar System.