If an observer has a height observed (Ho) that is less than the height calculated (Hc), what action should be taken?

When an observer's height observed (Ho) is less than the height calculated (Hc), it indicates that the observer is positioned lower than expected relative to the celestial object. In this case, the correct action is to adjust the position away from the celestial object.

This adjustment is essential because it helps the observer achieve an accurate fix on their position. Moving away from the celestial object generally means that the observer is correcting their course to align more closely with the calculated height, ultimately leading to a better understanding of their true geographic location. By doing this, it also compensates for any discrepancies caused by the observer's actual altitude versus the assumed height used in the celestial calculations.

In this context, measuring celestial navigation's alignment is crucial for achieving precision in positional fixing, and making the appropriate adjustments ensures improved navigation safety and reliability.