If they ask you about the islands you have visited, your answer may vary. You may have visited one, several, or none. We will cast serious doubt on the last case. Even if you think you have not visited an island, the following story will show you that you have probably been to one (many times). Its name: Null Island. The paradox: you will only find it on maps.

The island is not an island. Although there is no cartographic location under the name Null Island, we are looking at a cartographic location with zero latitude and zero longitude degrees. In other words, it is the point where the Earth’s prime meridian meets the equator. More precisely, if that is possible, it turns out to be a point in the Gulf of Guinea, a part of the eastern tropical Atlantic Ocean off the west coast of Africa.

The reason for its existence? To determine the geographic location of any point on a map, there must be a starting point (or 0-0 place) from which the rest of the points will be marked. The choice of a specific point on the map is related to the fact that the intersection of the zero meridian and the Equator is the starting point of the World Geodetic System 1984, the cartography on which the GPS system is based.

Why Gulf of Guinea? Because it’s part of the South Atlantic Ocean, something like the armpit of Africa. It’s the body of water just off the coast of where West Africa curves southward into Central Africa. The Gulf is right in the middle of any standard world map, and that’s no coincidence. It’s the meeting point of two geodetic baselines, the prime meridian and the equator. Or expressed as latitude and longitude: 0°N, 0°E.

And that’s exactly Null Island, a perfect anchor point for non-geographic data, but as you surely imagine, it’s not an island, but rather the colloquial name for the intersection of these two major orthodromes. In mathematics, and also in geodesy, an orthodox (or great circle) is the longest possible line that can be drawn around a sphere, thus dividing it exactly equally into two halves or hemispheres.

This is a buoy. No kidding. It’s not a real land mass, obviously, but if you literally sail into the Gulf of Guinea, at the intersection of the prime meridian and the equator, you’ll come across a large buoy. It’s the closest thing on the planet to Null Island.

Null Island (Buoy Station 13010 – also known as Soul)

Station 13010 – The weather-monitoring buoy known as Soul is part of the Atlantic Forecast and Moored Research (PIRATA) system, which monitors the tropical Atlantic Ocean. Along with 16 other buoys, the floating weather station measures things like wind speed, air temperature and humidity to help inform weather forecasts and climate models.

Therefore, in the real world, Null Island is a buoy, and in the virtual world it is a hypothetical point where misplaced data points are hidden.

The (non-)origin of the island. The equator, equidistant from the poles, gives the northern and southern hemispheres. The Greenwich Meridian, which divides the world into eastern and western hemispheres, is a more arbitrary line. Its status as the world’s prime meridian was not established until 1884, when it was established at the International Meridian Conference in Washington, D.C. The French abstained from the final vote because they had campaigned for the Paris meridian.

This was year zero for our point at zero north and zero east. What happened? Because of its remoteness, the location remained culturally unimportant until 2011, when it appeared in Natural Earth’s public map dataset as “Null Island.”

As they later explained in an explanation of the genesis or invention of Null: “We added a debugger country with an unspecified sovereign class called Null Island. It is an imaginary island of one square metre, located off the coast of Africa. The equator and the prime meridian intersect. Centering it at latitude 0 and longitude 0 is useful for flagging geocoding errors that appear as 0.0 in many services.”

Why were you there? Because you have definitely made a mistake while searching for a place, and not just once, but many times. Although it is not Null Island, it is a place name that is suitable for a frequently used location. A zero-zero reading often occurs as an error due to missing data or software glitches.

Deep down, something we use every day is actually responsible for our visits to Null: GPS. When we make a bad call, try to reach a place that doesn’t exist, or have a system error, we end up right there, at ground zero, on Null Island.

Image | Graham Curran

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