At sea, the natural horizon is used to align the sextant horizontally. AstroMedia has created a clever substitute for surveying on land: the artificial horizon enables relatively accurate measurements of a point above the mathematical horizon, even when it is not visible in the form of the horizon line, as is the case on the coast or at sea. With the help of a third mirror, a spirit level and the stamped cardboard components, the height can be measured independently of the natural horizon.
How it works: To determine the height of a point (star, mountain peak) above the mathematical horizon, you must check that the sextant is horizontal throughout the measurement by looking at the spirit level. You no longer need to pay attention to the unreflected image, but instead bring the reflected image with the targeted point to the height of the mark on the horizon mirror by swivelling the alidade. Then check once again that the sextant is horizontal and read off the measurement result.
