Texas Surveyors Practice Exam

Which of the following types of measurement can be considered geodetic north?

1. Magnetic north

2. Astronomic north

3. Grid north

4. All of the above

The correct answer is: All of the above

Geodetic north refers to the direction along the Earth's surface corresponding to the surface's geodetic meridian. It is a critical reference point for surveyors and should not be confused with other north references like magnetic or grid north. Astronomic north is the direction towards the North Pole, determined by looking at celestial objects. This measurement provides a solid reference from a geodetic standpoint, as it is based on the Earth's actual rotational axis. Magnetic north, while useful in navigation, is influenced by the Earth's magnetic field and varies based on geographic location and local anomalies. Although it is an important consideration for compass usage, it does not align perfectly with true north due to magnetic declination. Grid north is used in mapping and is aligned with the projection of the Earth's surface on a flat map. It is particularly relevant in specific coordinate systems but does not directly correspond to true north in all areas. Considering these definitions, all the described types of north provide context or points of reference related to geodetic measurements, making them relevant in various surveying and mapping applications. Therefore, stating that all the options are types of measurement that can be considered geodetic north acknowledges the context in which each is used in surveying practices.