Differences Between GDA94 and WGS84

GDA94 vs WGS84

From a person’s point of view, the Earth is a really large planet. It can hold up to more than 7 billion people (and counting). This oblate spheroid planet not only shelters humans but also other living things like animals and plants.

For many centuries, man has always been concerned about the place he is living in. He’s concerned about the size of his territory. We have heard stories of colonizations and land conquests because man has the innate desire of expanding his territory. When you possess a larger area, there are chances of having good trade in the market and a better route for transportation. To measure the approximate size of the Earth, man has come up with geodesy.

According to Webster, “geodesy” is the branch of applied mathematics which determines by observation and measurement the exact positions of points and the figures and areas of large portions of the Earth’s surface, the shape and size of the Earth, and the variations of terrestrial gravity. Man has been able to measure the size of the Earth with the application of mathematics, physics, and astronomy.

There are several applications of geodesy. It can be used for a country’s defense system. The coordinates and point locations in the geodetic map will help the defense system to determine the exact positions and distances in which they can manage their mapping and artillery. Geodetic maps are also beneficial in the field of global navigation, defensive missile operations, and satellite tracking.

Geodetic reference systems are used to be able to pinpoint or exactly locate one’s current position. Examples of geodetic reference systems are the GDA94 and WGS84. What are the differences between the GDA94 and WGS84?

GDA94

“GDA94” stands for “Geocentric Datum of Australia.” You can also call it “GDA.” As the name implies, the datum is a coordinate system specifically for Australia. This datum is a handy tool to keep track of different locations because it is composed of latitudes, longitudes, and east/north coordinates. GDA94’s coordinate system is centered at the heart of the Earth’s mass. In simple terms, it is geocentric.

Probably you are familiar with GPS (Global Positioning System). A GPS is installed on your cellphones. It is a device locator. GDA94 is a compatible tool for GPS. It is also superior from other existing Australian datum since it is based on a global framework. However, it is only fixed to a certain number of Australian reference points.

WGS84

“WGS84” stands for “World Geodetic System 1984.” It is the main geodetic reference system used by GPS. This geodetic system was developed for the DMA, or United States Defense Mapping Agency. “DMA” is now called the National Imagery and Mapping Agency or simply NIMA. Throughout time, the WGS84 system has been enhanced by its developers to cope with these modern times. It has come to a point wherein it is very close to the function of ITRF. Like the GDA94, it is geocentric.

The data stored in a WGS84 can now be downloaded to a computer. The data being received, computed, and processed of all GPS systems are read via the WGS84. WGS84 is also the datum for GIS software packages.

Summary:


  1. Geodesy is a branch of applied mathematics wherein the shape and size of the Earth are its main concerns.

  2. “GDA94” stands for “Geocentric Datum of Australia” while “WGS84” stands for “World Geodetic System 1984.”

  3. GDA94 is a coordinate system specifically for Australia. WGS84 is developed for the DMA or United States Defense Mapping Agency which is now called the National Imagery and Mapping Agency or simply NIMA. It is the main geodetic reference system used by GPS systems.