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.
It takes Earth 23 hours, 56 minutes and 4.091 seconds to completely rotate on its axis compared to the background stars. This amount of time is known as a sidereal... It takes Earth 23 hours, 56 minutes and 4.091 seconds to completely rotate on its axis compared to the background stars. This amount of time is known as a sidereal day. Earth rotates from west to east, which is why the Sun rises in the east and sets in the west. Earth's rotation is also slowing slightly with time, meaning that days were shorter in the past. This is due to the effect of the Moon on Earth's rotation. Atomic clocks show that a day is now about 1.7 milliseconds longer than it was a century ago.