Azimuth

Azimuth is the horizontal angle measured clockwise from the north direction to the direction of a specific point or object. Azimuth is an essential concept in navigation, geodesy, and surveying.

Types of azimuth:

• Astronomical azimuth - measured from true north (considering Earth's rotation axis)
• Geodetic azimuth - measured from geodetic north in a coordinate system
• Magnetic azimuth - measured from magnetic north (as shown by a compass)
• Grid azimuth - measured from grid north of the coordinate network

Importance of azimuth in surveying:

Azimuth is needed to:

• Determine direction between points
• Orient surveying instruments
• Calculate coordinates using the polar method
• Stake out boundaries in the field
• Develop maps and plans with correct orientation

Azimuth measurement:

Azimuth can be measured with various instruments:

• Compass - simple method for magnetic azimuth determination
• Theodolite or total station - precise angle measurements
• GNSS receiver - calculating direction between two points
• Astronomical methods - using Sun or star positions

Magnetic declination:

The difference between geodetic and magnetic north is called magnetic declination. In Latvia, this difference is approximately 7-8 degrees east, and it changes over time. This correction must be considered in precise surveying work.