Enabling GEOINT accuracy through geodetic, geophysical and photogrammetric sciences and content.
GridA grid, or more specifically a Grid Reference System, is a means by which to reference locations on the Earth's surface using a two dimensional Cartesian coordinate system referenced to a map projection. A grid coordinate defining a location consists of and is written as an ordered pair of x and y values expressed in linear units. Standard grid reference systems used by NGA and DoD are the Universal Transverse Mercator (UTM) and the Military Grid Reference System (MGRS). Both of these grid reference systems use the meter as the unit of measure and define an easting (x) and northing (y) referenced to a series of transverse Mercator map projections with specific projection parameters.
Graticule A graticule, or more specifically a Geographic Reference System, is a means by which to reference locations on the Earth using a system of angles. A geographic coordinate defining a location is usually expressed in angular units of latitude and longitude. Latitude (φ - phi) is the angle between the equatorial plane and the straight line that passes through the point in question and the center of the reference shape (WGS84 ellipsoid). Longitude (Λ - lambda) is the angle east or west of the reference meridian (Greenwich Prime Meridian) to another meridian that passes through the point in question. The standard geographic reference system used by NGA and DoD are latitude and longitude expressed in sexagesimal (base 60) numbering system.
The Universal Polar Stereographic (UPS) Systems coordinates are based on a family of two Polar Stereographic map projections, one for each pole.
UPS North, 100km MGRS Letters: top image
UPS South, 100km MGRS Letters: bottom image
Latitude/longitude is a geographic reference system used to define positions on the Earth. It consists of angles of latitude that are measured from the center of the Earth and are referenced starting at the Equator, which is assigned 0°. Moving north and south of the Equator, latitudes increase in number from 0° to 90° at the two poles. Angles of longitude are also measured from the center of the Earth and are referenced starting at the Prime Meridian, which is assigned 0°. Moving east and west of the Prime Meridian, longitudes increase in number from 0° to 180°. A Latitude/Longitude coordinate must include Latitude and Longitude parts in conjunction to define a location.
Following the sexagesimal, base 60, system, degrees can be subdivided into 60 minutes, and minutes can be subdivided into 60 seconds, for the purpose of increased precision level. This can result in several formats, such as degrees-minutes-seconds, degrees-decimal minutes, and decimal degrees. The more digits included in the coordinate string, the higher the precision level.
To indicate hemisphere, the abbreviations for north, south, east, and west (NSEW) are commonly used. An alternate manner to indicate hemisphere is to use the minus sign for latitudes in the southern hemisphere and longitudes in the eastern hemisphere. The plus sign is usually not written and indicates northern or western hemisphere.
The World Geographic Reference System (GEOREF) is an area reference system used for interservice reporting for air defense and strategic air operations. It provides a method of expressing position in a form suitable for reporting and plotting and may be applied to any map or chart graduated in latitude and longitude. Click here for a detailed description of the GEOREF system.
The USNG is a coordinate reference system used for locating points and areas on the surface of the Earth and is functionally equivalent to the Military Grid Reference System (MGRS). The main difference between the two systems is in the method for specifying the datum. In MGRS, an alternate lettering scheme (Old Letters) is used for the 100,000-meter Square Identifier when the position is referenced to an older datum. The USNG does not use the alternate lettering scheme, but simply specifies the datum after the position reference. For example, a position on the NAD27 datum is reported in the two systems as follows:
The NGA Office of Geomatics maintains the following specialty grids:
Transformation A transformation, or more specifically a geodetic datum transformation, is a change in a coordinate based on to what geodetic datum a coordinate is referenced. The NGA and DoD approved geographic translator to perform geodetic datum transformations is MSP GEOTRANS.
Conversion A conversion, or more specifically a coordinate conversion, is a change in coordinate data from one reference system to another. The NGA and DoD approved geographic translator to perform coordinate conversions is MSP GEOTRANS.
Geodetic ResearchGeodetic Research is the attempt to discover missing geodetic metadata in regards to coordinate data or maps to give them added spatial context. In most cases, if there is missing geodetic metadata, geodetic research is the process by which geodetic scientists use tools such as GIS, geographic translators, calculations, library of geodetic information and open source to learn likely geodetic reference ellipsoids/datums, grid/map projection parameters, a means by which to convert/translate the information to an NGA geodetic standard and a way to properly display the information and verify its location.
Geodetic PackageA Geodetic Package is a collection of geodetic information for a specific NGA standard map product to ensure that it has the timely and necessary information to properly place reference system lines, proper reference system labels and magnetic information. Geodetic Packages are required of all NGA standard map products and the software program to create them is GEOPAK.
While GEOTRANS is the NGA recommended and supported software package for Datum Transformations and Coordinate Conversions, there are occasions when something else is requested or proposed, and needs to be tested. For such occasions, software developers are invited to download the following ZIP collection of test files. These are files created by NGA geodesists working independently of GEOTRANS. The files are simulated data (not measurements) and provide a higher accuracy standard for software performance than does GEOTRANS as of 3/25/2009 for the algorithms treated. Also, in some cases, they allow input values that GEOTRANS does not. Therefore, if developers have not carefully defined the domain of valid inputs and implemented the corresponding input checking, these tests are likely to reveal the lack thereof. The files "Instructions.doc" and "Release_Notes.doc", found in the ZIP, contain further information. This is an ongoing project, and more tests will be added in later releases. Comments are welcome at the e-mail address below.
A geodetic package is a collection of geodetic metadata used for grid,
graticule and magnetic verification for all NGA standard map products.
The software to create a geodetic package is GEOPAK and is available at the NGA GEOINT APP Store. PKI certs required.
The Tiled Image Converter is a GUI based program built by the
Naval Research Laboratory that is capable of converting entire
pyramids of raster tiles away from the input map projections into one
of the output map projections. The input map projections are web
Mercator (also known as EPSG::3857), WGS 84 Plate Carree (also known
as EPSG::4326), and Mercator. The output map projections are Mercator
and Plate Carree. The software is available at the NGA GEOINT APP Store. PKI certs required.
MSP GEOTRANS is the NGA and DOD approved coordinate converter and
datum translator. The user-friendly GUI has features including batch
conversion capability, a choice of precision levels and the capability
to add your own datum. MSP GEOTRANS can be run as an online web app or
downloaded to run as a stand-alone application. Available downloads
are listed in the table below. Click here to use the NGA web version.
Windows End User (Recommended For Most Users): The Windows End-User version is intended for end-users that operate on a Windows platform. It includes everything necessary to run GEOTRANS (including online help). It does not include the source code. A Windows installer makes the installation easy and it allows the user to create a shortcut to GEOTRANS that can be placed at a specified location. Windows 7 Users: Download the desired version, double click on the install.exe file, and follow on screen instructions; your computer will be re-booted after installation.
IMPORTANT: Before downloading the 64-bit version, verify that 64-bit Java is installed on your system at: C:\Program Files\Java. If 64-bit Java is not installed, then download and install 64-bit Java before downloading MSP GEOTRANS, or instead download and install the 32-bit version of MSP GEOTRANS.
The Linux End-User version is intended for end-users that operate on a Linux platform. This version includes everything necessary to run GEOTRANS, including online help. This version does not include source code.
The Software Developers version is intended for software developers. This version is available for both Windows and Linux platforms, and includes everything included in the End-Users version plus all of the source code, documentation and a programmer's guide.
The Developer MGRS Only version is for software developers who only need the MGRS capability. This version is available for both Windows and Linux platforms, and includes MGRS, UTM, UPS, Transverse Mercator and Polar Stereographic modules, source code and documentation. This version does not include GEOTRANS executables.
The Developer Master version is intended for software developers, and includes the GEOTRANS executables for all platforms, all source code and documentation. The difference between the Windows and Linux master is the zip method.
The MSP GEOTRANS app is intended to be installed on Android 2.3 and later OS devices. The MSP GEOTRANS App is available through the NGA GEOINT APP Store on the SBU. A GEOINT Online account is required to access the GEOINT App Store. The MSP GEOTRANS app may also be downloaded using the link to the left.
NOTE: If the filename is different after downloading, be sure to rename the file for decompression purposes. After downloading one of the MSP GEOTRANS files, you may optionally verify that the downloaded file exactly matches the download file stored on the distribution server by generating an MD5 digest of your downloaded file. The MD5 digest value for your downloaded file must exactly match the MD5 digest published on this web page for the files to be the same.
Having trouble starting GEOTRANS? Here
are some suggestions
If you have installed GEOTRANS and are unable to get it to start (no message given) you may need to download the MS Visual C++ Redistributable Package. This software is normally included on a computer, but system configurations do vary. Please read the instructions for installing GEOTRANS on a Network Drive.
MS Visual C++ Redistributable Package for 32-bit user download: http://www.microsoft.com/en-us/download/details.aspx?id=5582
MS Visual C++ Redistributable Package for 64-bit user download: http://www.microsoft.com/en-us/download/details.aspx?id=14632
NOTE: Java 32-bit and 64-bit may be required to run MSP GEOTRANS. GEOTRANS 3.7 was built using Java JDK 1.8 update 72. The latest releases of Java can be found at Orcale.com. Should you encounter a Windows Error 2 condition during MSP GEOTRANS install, this error usually occurs because the wrong bit-level for Java was selected. Especially with Java 1.8, the Windows environment variable for PATH is often not set correctly. You may try the following procedure to correct the condition:
Contact the MSP/GEOTRANS Help Desk
For assistance with MSP GEOTRANS software, including questions about source code, please contact the NGA Enterprise Service Center (ESC) at 800-455-0899 or email MSP_Help@nga.mil (Unclassified content only).
Services require PKI certs and allow visualization via the IC Portal or ArcGIS desktop (download). After selecting the link below, additional viewing options may be available by following the link under the "Map Contents" heading.
Air Target Chart (ATC) is a subdivision of the World Aeronautical Chart (WAC). There are 25 ATC per WAC. ATC is visible at scale of 1:9,000,000 and larger
GARS is the standardized battlespace area reference system across DoD which will impact the entire spectrum of battlespace deconfliction.
Latitude/Longitude is a geographic coordinate measurement used in mapping, charting, and geodesy to reference positions on the Earth.
MGRS is an alpha-numeric system for expressing UTM/UPS. A single alpha-numeric value references a position that is unique for the entire earth.
Rapid Worldwide Area Collection (RWAC) is a ten digit identifier that uniquely identifies a four-corner geographic coordinate box configured either as a 3x3nm or 9x9nm box. RWAC is visible at scale of 1:1,000,000 and larger
World Aeronautical Chart (WAC) is a chart system overlaying the Earth's surface bounded by pairs of parallels at 4 degree increments and meridians at integral degree boundaries chosen to give approximately 360 nautical mile regions.
World Target Mosaic (WTM), also referred to as World Aeronatical Chart (WAC) Target Mosiac, is a subdivision of the Air Target Chart (ATC) and is the basic collection unit for the Broad Area Search (BAS) imagery. There are 16 WTM per ATC. WTM is visible at scale of 1:2,000,000 and larger