![]() ![]() This figure to the right shows the main meridians, as seen from the North Pole. The 180-degree longitude line is opposite the prime meridian and is the same whether traveling east or west. Rather than being preceded with positive or negative signs, the lines of longitude are often designated in terms of their direction, as in Longitude 45 degrees E or Longitude 45 degrees W, for east and west, respectively. The Earth is divided equally into 360 degrees of longitude, with 180 degrees of longitude to the east of the prime meridian (+180) and 180 degrees of longitude to the west of the prime meridian (-180). This figure shows the prime meridian, as seen from the North Pole. Longitude values indicate the angular distance between the prime meridian and points east or west of it on the surface of earth. For this reason, it’s referred to as the prime meridian. The meridian that runs through Greenwich, England is considered to be 0 degrees of longitude. The degrees assigned to longitudes are different from what are used for latitudes. Each line of longitude is part of a great circle that wraps around the circumference of the earth. The lines of longitude, also called meridians, run perpendicular (at right angles, or 90 degrees) to the lines of latitude and all pass through both poles. Longitude is a geographic coordinate that specifies the east-west position on the surface of Earth. When the directional designators are omitted, northern latitudes are given positive values and southern latitudes are given negative values. It is 90 degrees to the south of the Equator, or 90 degrees south latitude. The South Pole works the same way as the North Pole. For example, the latitude halfway between the Equator and the North Pole is at 45 degrees, so it’s considered to be at 45 degrees north latitude, as shown in the following figure. ![]() Latitudes between the Equator and North Pole are marked accordingly. As a result, the North Pole is considered to be at 90 degrees north latitude. There are 90 degrees of latitude between the Equator and the North Pole. All parallels are equally spaced to each other. Because the lines are parallel to the Equator, they’re also referred to as parallels. The lines of latitude represent values in whole degrees. ![]() Latitude values indicate the angular distance between the Equator and points north or south on the sphere.Ī line of latitude is an imaginary line connecting all the points with same latitude value. The Equator is an imaginary line on the earth’s surface that circles the earth, bisecting the distance between the poles, as shown in the following figure:īecause the Equator lies at midpoint between the poles, it is considered to be at 0 degrees, which makes it the starting point for measuring latitude. The North and South poles lie at the ends of that axis. It is common knowledge that earth spins on an axis. This figure provides an overview of how we obtain our coordinates in relationship to the earth’s center: What is latitude coordinate? Coordinates are measured in degrees and represent angular distances calculated from the earth’s center. We usually use spatial data to store coordinates, topology, or other data that can be mapped.īecause Earth is a sphere, we use latitude and longitude coordinates to define a location on its surface. Spatial data, also known as geospatial data or geographic information, is data that identifies the geographic location of features and boundaries on Earth. This functionality is also available in Azure SQL Database and Azure Managed Instances as well as all editions of SQL Server. At the same time, Microsoft added the functionality necessary to access and index spatial data, provide cost-based optimizations, and support operations such as the intersection of two spatial objects. Microsoft added support in SQL Server 2008, with the introduction of native spatial data types to represent spatial objects. Database systems such as IBM, DB2, and Oracle have supported spatial data for some time. With the introduction of so many handheld devices that support features such as GPS and maps, the need to store spatial data in a relational database is greater than ever. ![]()
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