🔍 Key Concepts

• Ex-meridian sight method for latitude (relationship between latitude, declination, and meridian altitude) • Proper reduction of sextant altitude to Ho (index error, dip, and altitude corrections) • Effect of chronometer error (slow/fast) on converting to correct UTC for ex-meridian correction

💭 Think About

• First, focus only on getting a clean Ho from the given hs. What is the sign of the index error when it is 1.5' "on the arc" and how does that affect the altitude? • Think about the basic meridian passage formula: if the star were exactly on the meridian, how would latitude relate to declination and observed altitude? Then consider what changes when the star is a little before or after the meridian (ex‑meridian). • Ask yourself: how does the small time difference from meridian passage affect the altitude you observed, and is the ex‑meridian correction added to or subtracted from the approximate latitude?

✅ Before You Answer

• Be sure you use the correct sign of index error and calculate dip for 44 ft before doing any further work. • Confirm whether the star’s declination is north or south, and decide whether latitude should be same name or contrary name to declination for this sight. • Before choosing a multiple-choice answer, estimate whether the ex‑meridian correction should make the latitude larger or smaller than your DR latitude of 30° 26.0' N. This helps you eliminate unreasonable options.