Updated:
24 December 2007
Geodetic and GPS Data
National Geodetic Database (NGDB)
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The NGDB is a national archive of about 23,000 geodetic survey marks of national interest, in Australia and its external territories (including Antarctica).
Coordinates of these marks are held in the Geocentric Datum of Australia (GDA) as well as the two previous versions of the Australian Geodetic Datum (AGD66 and AGD84). Not all stations have coordinates in all datums.
State and Territory agencies can supply recent and additional information for their area of responsibility.
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Australian Height Datum (AHD)
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On 5 May 1971, Geoscience Australia's predecessor, the then Division of National Mapping, on behalf of the National Mapping Council of Australia (NMC), carried out a simultaneous adjustment of 97,230 kilometres of two-way levelling. This levelling was constrained to mean sea level.
Mean sea level for 1966–68 was assigned the value of zero on the Australian Height Datum at 30 tide gauges around the coast of the Australian continent. The resulting datum surface, with minor modifications in two metropolitan areas, is the Australian Height Datum (AHD). Geoscience Australia maintains an archive of the basic AHD network. State and territory agencies can supply recent and additional information for their area of responsibility. |
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Astronomical Information
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Astronomical phenomena including sun, moon and planet data.
On Geoscience Australia's web site you may:
- Compute your own sunrise/sunset times
- Compute your own moonrise/moonset times
- Compute your own sun and moon positions
- Browse moon phase data
- Browse astronomic data files
If required, certificates for astronomical phenomena can also be provided. |
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AUSGEOID
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AUSGeoid98 is the latest in a series of national geoid models for Australia produced by Geoscience Australia. AUSGeoid98 consists of a 2 minute by 2 minute grid (approximately 3.6 km) of geoid-ellipsoid separations (N Values) in terms of the GRS80 ellipsoid, which is also used for the new Geocentric Datum of Australia (GDA94). These values are suitable for use with GPS and will significantly improve the achievable accuracy of AHD height transfer using GPS. |
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Australian Regional GPS Network
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The ARGN consists of 15 permanent geodetic quality GPS receivers, on geologically stable marks, in Australia and its External Territories.
These sites provide the geodetic framework for the spatial data infrastructure in Australia and its External Territories. Data from these sites contributes to the International GPS Service (IGS) and provides input for the measurement of earth processes, such as crustal dynamics and sea level rise. |
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Satellite Laser Ranging (SLR) Network
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Satellite laser ranging solutions are computed monthly. These monthly solutions are submitted to the International Earth Rotation Service (IERS).
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Space Geodesy Analysis - Global Positioning System
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An Australian and Antarctic regional GPS solution is computed daily. Daily solutions are combined into weekly solutions and are contributed to the International GPS Service (IGS) as Geoscience Australia's contribution to International Reference Frame Densification. |
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Space Geodesy Analysis - SINEX - Satellite Laser Ranging
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Geoscience Australia operates laser ranging stations at Mount Stromlo, ACT, and Yarragadee, WA. It coordinates their activities and liaises with the International Laser Ranging Service (ILRS), Western Pacific Laser Tracking Network (WPLTN) and the NASA Solid Earth and Natural Hazards (SENH) Projects to define observing programs and quality requirements.
Laser ranging provides global satellite and lunar laser ranging data and their related products to support geodetic and geophysical research activities as well as International Earth Rotation Service (IERS) products important to the maintenance of an accurate International Terrestrial Reference Frame (ITRF). |
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Standards and Practices for Horizontal and Vertical Control Surveys
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The Standards and Practices for Control Surveys, frequently referred to as Special Publication 1 (SP1), is produced by Geoscience Australia for the Intergovernmental Committee on Surveying and Mapping (ICSM). There have been several editions since this publication was first produced in 1966, resulting in the current version.
It provides clear standards of accuracy for control surveys. SP1 aims to achieve uniformity of standards throughout all national and state control networks in Australia. |
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Geocentric Datum of Australia (GDA) - Technical Manual
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The GDA Technical Manual replaces the Australian Geodetic Datum Technical Manual, which was published in 1985 to replace both the Australian Map Grid Technical Manual and Geoscience Australia Council Special Publication - The Australian Height Datum.
The new Geocentric Datum of Australia Technical Manual is principally designed to explain all facets of the new Geocentric Datum of Australia and continues the tradition of providing complete formulae and worked examples in computer spreadsheets.
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About Geodetic and GPS Data Products
Geodesy is a dynamic application of scientific methods in support of many professional, economic and scientific activities and functions, ranging from land titling to mineral exploration; from navigation, mapping and surveying to the use of remote sensing data for resource management; and from the construction of dams and drains to the interpretation of seismic disturbances.
Geoscience Australia is the Commonwealth focal point for coordination of geodetic information and data and is working with State agencies, the Intergovernmental Committee on Surveying & Mapping (ICSM) and industry groups towards the provision of the best possible data.
The Geoscience Australia Geodesy Program monitors the horizontal and vertical motion of the Australian landmass and contributes data to the global scientific effort to monitor the Earth's changing shape and motion. This data provides a uniform, accurate basis for all spatial data in Australia and its offshore territories.
Geoscience Australia operates satellite laser ranging stations at Mt Stromlo in the Australian Capital Territory and Yarragadee in Western Australia. Ranked amongst the best in the world, these stations measure precise distances to satellites by timing the reflected flight of laser beam pulses. These precise measurements allow Geoscience Australia to calculate precise orbits for artificial satellites, monitor the Earth's gravity field, and measure the oscillation of the Earth about its axis.
Geoscience Australia offers geodetic products and services for a range of professional and personal uses. One of the most popular services is the online astronomical information, such as the sun and moon rising and setting times and the Astronomic Certificate. This is a legal document used for certifying the time of an astronomic event, such as a court seeking a ruling on whether the sun was in a driver's eyes in the late afternoon.
Although much of the other geodetic data is of immediate interest to a specialist technical audience, it is fundamental to Australia's geographic coordinate systems and the spatial industry.
Some of the documents on this webpage may be in PDF Format. Please download the Free PDF reader from Adobe to view these files.