Title: Equator
Content: Equator An equator of a rotating spheroid (such as a planet) is its zeroth circle of latitude (parallel). It is the imaginary line on the spheroid's surface, equidistant from its poles, dividing it into northern and southern hemispheres. In other words, it is the intersection of the spheroid's surface with the plane perpendicular to its axis of rotation and midway between its geographical poles. On Earth, "the Equator" is about long, of which 78.8% lies across water and 21.3% over land. Indonesia is the country straddling the greatest length of the equatorial line across both land and sea. The name

Title: Equator
Content: is commonly modeled as a sphere flattened 0.336% along its axis. This makes the Equator 0.16% longer than a meridian (a great circle passing through the two poles). The IUGG standard meridian is, to the nearest millimetre, , one arc-minute of which is , explaining the SI standardization of the nautical mile as , more than less than the geographical mile. The sea-level surface of the Earth (the geoid) is irregular, so the actual length of the Equator is not so easy to determine. "Aviation Week and Space Technology" on 9 October 1961 reported that measurements using the Transit IV-A

Title: Latitude
Content: latitude, to avoid ambiguity with the geodetic latitude and the auxiliary latitudes defined in subsequent sections of this article. Besides the equator, four other parallels are of significance: The plane of the Earth's orbit about the Sun is called the ecliptic, and the plane perpendicular to the rotation axis of the Earth is the equatorial plane. The angle between the ecliptic and the equatorial plane is called variously the axial tilt, the obliquity, or the inclination of the ecliptic, and it is conventionally denoted by . The latitude of the tropical circles is equal to and the latitude of the

Title: Spherical coordinate system
Content: reference meridian (most commonly the IERS Reference Meridian), so its domain is . For positions on the Earth or other solid celestial body, the reference plane is usually taken to be the plane perpendicular to the axis of rotation. The polar angle, which is 90° minus the latitude and ranges from 0 to 180°, is called colatitude in geography. Instead of the radial distance, geographers commonly use altitude above or below some reference surface, which may be the sea level or "mean" surface level for planets without liquid oceans. The radial distance can be computed from the altitude by adding

Title: Earth radius
Content: The equatorial radius is often used to compare Earth with other planets. The Earth's polar radius , or semi-minor axis, is the distance from its center to the North and South Poles, and equals . The distance from the Earth's center to a point on the spheroid surface at geodetic latitude is: where and are, respectively, the equatorial radius and the polar radius. There are two principal radii of curvature: along the meridional and prime-vertical normal sections. In particular, the Earth's "radius of curvature in the (north–south) meridian" at is: This is the radius that Eratosthenes measured. If one point

Question: What name is given to your angular distance on the Earth's surface relative to the equator?
Answer: Latitude