• Mean equatorial radius $a$ defined in EGM08: 6378.1363 km.
• Semiminor axis $b$ defined in EGM08: Distance from the Earth’s center to the North or South Pole. It is 6356.751 km.
• Flattening is defined as $\frac{a-b}{a} = \frac{1}{298.257}$.
• Eccentricity is defined as: $e = \sqrt{1 - \frac{b^2}{a^2}} = 0.081819$.
• Rotational velocity: $7.292115 * 10^{-5}$.
• Oblate spheroid meant that the semimajor axis is equal to the equatorial axis; semiminor axis is equal to the polar radius. The Earth’s shape is approximately an oblate spheroid.
• The differences between geocentric latitude and geodetic latitude:
  • geocentric latitude: equatorial plane and radius vector from Earth’s center to the point.
  • geodetic latitude: equatorial plane and normal to the reference ellipsoid.
• Example 3.1 determines the site coordinates from geodetic latitude and the altitude of mean sea level.