Equator

The sun on the Equator

How to use it

1. The line is drawn in orange across the whole map as soon as the page opens.
2. Pan and zoom to follow it. On the web map's Mercator projection, parallels are straight horizontal lines and meridians straight vertical ones.
3. Under the map, read the list of countries whose land the line crosses and the notes about the line.
4. Use the other line pages linked below to compare positions, or the miles per degree calculator for the length of a degree at this latitude.

Why the Equator is where it is

The equator is the only parallel that is a great circle, the widest circle you can draw on the globe. Its plane passes through the Earth's center at right angles to the axis, which makes it the natural zero for latitude.

Near the equator the sun rises and sets almost straight up and down, so twilight is short and day length stays close to 12 hours all year. The noon sun is never more than 23.4° from straight overhead.

How long the line is

A parallel is a circle whose radius is the distance from the Earth's axis. On the WGS84 ellipsoid that radius is N · cos φ, where N is the prime vertical radius of curvature, which at 0.0000° is 6,378,137 m. The circumference 2π · N · cos φ comes to 40,075.0 km.

One degree of longitude along it is 111.32 km, or 69.17 miles. The miles per degree calculator gives the same figure for any latitude.

Countries on the line

Testing a point every 0.02° along the line against the Natural Earth 1:50m outlines finds land in 10 countries: Ecuador, Colombia, Brazil, Gabon, Republic of the Congo, Democratic Republic of the Congo, Uganda, Kenya, Somalia, Indonesia. At that scale small islands drop out, so the list covers the mainland and larger islands.

• The equator of the WGS84 ellipsoid is 2π × 6,378,137 m = 40,075.017 km long.
• Island nations such as the Maldives and Kiribati have atolls on or near the line that are too small to show at the 1:50m scale.

The United States and this line

No US state touches the equator. The state capital closest to it is Honolulu at 21.307° N, which is 1,465 miles north of the line along a meridian. Denver's capitol sits 2,734 miles north of it.