The false origin may or may not be aligned to a known real-world coordinate, but for the purpose of data capture, bearings and distances can be measured using the local coordinate system rather than global coordinates. Local coordinate systems are often used for large-scale (small area) mapping. A map projection contains the mathematical calculations that convert the angular geodetic coordinates of the GCS to Cartesian coordinates of the planar PCS system.ĭownload the list of supported projected coordinate systems.Ī geographic coordinate system (left) measured in angular units is compared to a projected coordinate system (right) measured in linear units for the same location in the Atlantic Ocean.Ī local coordinate system uses a false origin (0, 0 or other values) in an arbitrary location anywhere on earth. A projected coordinate system is composed of a geographic coordinate system and a map projection together. Projected coordinate systems (PCS) are planar systems that use linear measurements for the coordinates rather than angular units. The location of data is expressed as positive or negative numbers: positive x- and y-values for north of the equator and east of the prime meridian and negative values for south of the equator and west of the prime meridian.ĭownload the list of supported geographic and vertical coordinate systems. Geographic coordinate systems (GCS) are based on a three-dimensional ellipsoidal or spherical surface, and locations are defined using angular measurements, usually in decimal degrees, measuring degrees of longitude (x-coordinates) and degrees of latitude (y-coordinates). You can determine which type of coordinate system your data uses by examining the layer's properties. Horizontal coordinate systems can be of three types: geographic, projected, or local. Horizontal coordinate systems locate data across the surface of the earth, and vertical coordinate systems locate the relative height or depth of data. Coordinate systemsĭata is defined in both horizontal and vertical coordinate systems. Identifying this measurement system is the first step to choosing a coordinate system that displays your data in its correct position in ArcGIS Pro, in relation to your other data. The coordinates can be specified in many ways, such as decimal degrees, feet, meters, or kilometers any form of measurement can be used as a coordinate system. These numbers are part of a coordinate system that provides a frame of reference for your data to locate features on the surface of the earth, to align your data relative to other data, to perform spatially accurate analysis, and to create maps.Īll spatial data is created in a coordinate system, whether it is points, lines, polygons, rasters, or annotation. Spatial data is similar, but it also includes numerical information that allows you to position it on earth. The following table lists the ephemerides of The Moon computed for the past and next 7 days, with a 24 hours interval.Data usually comprises an array of numbers. Source: JPL Small-Body Database Physical Parameter The following shows the known values of the most important physical parameters of The Moon. Today the Moon is in First Quarter phase and is currently in the constellation of The first human landing on the Moon was in 1969 during NASA's Apollo 11 mission, and since then, several missions have been sent to study the Moon's geology, surface features, and potential for future human exploration and colonization. ![]() The Moon has been used as a celestial body for human exploration and scientific study. It has a day length of 29.5 Earth days, which is also the length of its orbital period around Earth. ![]() The Moon has no atmosphere and no magnetic field, which means that it is exposed to the solar wind and cosmic rays. The Moon's surface is covered in craters, mountains, and plains, with the largest feature being the Imbrium Basin. It has a diameter of 3,474 kilometers and a mass of 7.34 x 10^22 kilograms, making it about 1/81st the mass of Earth. The Moon is Earth's only natural satellite and is the fifth-largest satellite in the solar system.
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