aardmiddelpunt

Aardmiddelpunt is a Dutch term that commonly refers to the center of mass of the Earth, also known as the geocenter. It is the point in space where the Earth’s mass can be considered to be concentrated for purposes of gravity calculations and for defining a geocentric reference frame. In practice, the geocenter serves as the origin of geocentric coordinate systems such as WGS84 used in GPS and mapping, and as a reference in celestial mechanics related to the Earth.

Location and variability: The geocenter is not a fixed point on the surface; it is determined by the distribution of mass inside the Earth (crust, mantle, core) and can shift slightly as mass is redistributed by processes such as plate tectonics, mantle flow, changes in ocean and atmospheric mass, and large hydrological cycles. The concept is distinct from the Earth–Moon system barycenter, which is the common center of mass around which both bodies orbit; that barycenter lies inside the Earth but offset from its geometric center, and its position varies with the Moon’s orbit.

Use and importance: Understanding the aardmiddelpunt is essential in geodesy, astronomy, and spaceflight navigation, where precise knowledge of Earth’s position and orientation is required. It underpins the definition of the geoid, the reference surface used to measure elevations and mean sea level, and provides the basis for geocentric coordinate systems used in modern mapping and satellite positioning.

See also: center of mass, geocenter, geoid, WGS84, barycenter.