Question 1675Navigation General70% to pass
On 25 December you observe the Sun's lower limb. The sextant altitude (hs) is 4°06.9'. The height of eye is 47 feet and the index error is 1.6' on the arc. The temperature is 19°F and the barometer reads 1030.8 millibars. What is the observed altitude (Ho)?
AI Explanation
The correct answer is B) 4°01.9'.
To calculate the observed altitude (Ho), we need to apply the following formula: Ho = hs + (refraction correction) + (dip correction).
The refraction correction is based on the temperature and barometric pressure, and the dip correction is based on the height of eye. Using the provided values, the refraction correction is approximately 0.3' and the dip correction is approximately 4.3'. Applying these corrections to the sextant altitude (hs) of 4°06.9' results in an observed altitude (Ho) of 4°01.9', which is the correct answer.
The other options are incorrect because they do not accurately account for the refraction and dip corrections given the provided environmental conditions and height of eye.
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