On 6 March your 1854 zone time DR position...

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Question 1 of 2066636eea28f7522a1c51ae3b

On 6 March your 1854 zone time DR position is LAT 23° 51.5' N, LONG 73° 14.0' W. At that time you observe Polaris with a sextant altitude (hs) of 24° 16.5'. The chronometer time of the sight is 11h 52m 40s, and the chronometer error is 01m 56s slow. The index error is 5.0' on the arc, and the height of eye is 43.5 feet (13.3 meters.) What is your latitude by Polaris?

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🔍 Key Concepts

• Polaris latitude method – Polaris’ altitude is approximately equal to your latitude, with small corrections • How to correct sextant altitude (hs) to apparent altitude (Ha) and then to observed altitude (Ho): index correction, dip, and refraction • Apply the standard Polaris corrections (northern hemisphere) based on LHA Aries or date to adjust Ho to latitude

💭 Think About

• First, carefully convert the sextant altitude (hs) to the observed altitude (Ho). Think step‑by‑step: index error, dip for height of eye, and any necessary altitude corrections. • Next, recall how Polaris differs from other stars: instead of doing a full sight reduction for intercept, you use a short set of Polaris corrections to get latitude directly. • Compare your final corrected Polaris altitude plus/minus the small tabular corrections with the DR latitude. Ask yourself: is the resulting latitude reasonable and close to your DR position?

✅ Before You Answer

• Be sure you apply the index correction with the correct sign: 5.0' "on the arc" means what direction of correction? • Confirm you are using the correct dip (height of eye) table for 43.5 ft (13.3 m) – don’t mix feet and meters. • When you look up the Polaris correction for the date (early March), double‑check you are applying it with the correct sign (add vs. subtract from Ho) before comparing to the answer choices.

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