When corrections are made for refraction, what happens to the apparent position of a celestial body?

When corrections are made for refraction in the context of celestial navigation, they are typically subtracted from the observed position of a celestial body. This is because atmospheric refraction causes celestial objects to appear higher in the sky than they actually are. Therefore, without making the necessary corrections, one would mistakenly assume the body is at that elevated position instead of its true position.

By subtracting the refraction correction from the observed angle, you adjust for the distortion caused by the atmosphere and accurately determine the true angle of the celestial body as seen from the Earth's surface. This adjustment is crucial for precise navigation and positioning as the computed positions are reliant on accurate angular measurements.