Rotating Events in Our Time
The majority of people are aware that the Earth rotates around the Sun every 24 hours. However it is not widely known that the speed at which the Earth rotates differs slightly. This means that a given day may be shorter or longer than expected. This is the reason timekeeping atomic clocks which maintain standardized time must be periodically adjusted, adding or subtracting a second. This change is called the leap second. This article will explain how this shift happens, and why it is important to our daily schedules.
One of the most common rotating events is precession, a periodic wobble of Earth’s central axis of motion, similar to as a spinny, slightly off-center toy top. The axial direction change relative to fixed stars (inertial space) is observed for a period of 25,771.5 years. It’s also responsible for switching the directions of cyclones across the Northern and Southern Hemisphere. Other rotating events include free nutation, the Chandler wobble, and polar movement.
In addition, to these periodic events, the speed of the rotator can be affected by weather conditions and other factors, including earthquakes. If the core of Earth moves faster, the day will feel shorter. This change is caused by tides acting on the surface of the Earth and gravity pulls from other objects in the Solar System, such as Jupiter and Saturn. This is the reason it’s crucial to take into account the Earth’s rotational velocity when designing fun park rides such as Ferris wheels and Carousels.