Earth Polar Radius
The Earth's polar radius is the distance from the center of the Earth to the North or South Pole. It measures the Earth’s radius along its rotational axis.
Its value is approximately 6,356.8 kilometers (about 3,949.9 miles).
The Earth is an oblate spheroid, so the polar radius is slightly shorter than the equatorial radius due to the planet's flattening at the poles.
This measurement is crucial for geodesy, understanding Earth’s shape, and satellite navigation.
Key facts:
Polar radius ≈ 6,356.8 km
Smaller than equatorial radius by about 21.3 km
Important for precise Earth modeling and mapping
The difference between the polar and equatorial radius reflects the Earth’s rotation and its effect on the planet’s shape.
Fermi
A fermi is a unit of length used in nuclear physics to measure extremely small distances, such as the size of atomic nuclei. It is equal to 1 femtometer (fm), which is 10⁻¹⁵ meters.
The unit is named after the Italian physicist Enrico Fermi, known for his work in nuclear physics.
Key facts:
1 fermi = 1 femtometer = 10⁻¹⁵ meters
Used to measure nuclear dimensions and particle sizes
Essential in the study of nuclear and particle physics
The fermi is vital for describing distances at the subatomic scale, much smaller than atoms and molecules.
No conversions available for length.