Lưu ý: Bản dịch của mục này hiện đang được kiểm tra chất lượng, vì vậy một số nội dung tạm thời chỉ hiển thị bằng tiếng Anh.
Mục từ này chưa được dịch sang ngôn ngữ của bạn, vì vậy nội dung gốc được hiển thị bên dưới.
geoid
This term describes a complex, irregular surface that represents the actual gravitational potential of the Earth. It serves as the primary baseline for geodesy, allowing scientists to determine precise altitudes by comparing a measured ellipsoidal height to the geoid height.
Because it is a specialized scientific concept, the word is used almost exclusively in technical contexts such as cartography, satellite altimetry, and geophysical surveying. It is distinct from a perfect sphere or an ellipsoid, as it accounts for the uneven distribution of mass within the planet.
Ý nghĩa
Ví dụ
The geoid is often used as a reference surface for measuring altitude.
Wait, so the geoid is not a perfect sphere because of gravity variations?
The difference between the ellipsoid and the geoid is known as geoid height.
Satellite missions provide high resolution data to map the global geoid.
I need to understand how the geoid affects GPS altitude readings.
The geoid represents an equipotential surface of the Earths gravity field.
Imagine the entire planet covered in water at rest; that shape is the geoid.
Geodesists study the geoid to better understand the distribution of mass within the Earth.