The line of position determined from a sight...

🔍 Key Concepts

• Altitude-intercept method (Marcq St. Hilaire method) and how a line of position (LOP) is normally plotted from a celestial sight • What a very high observed altitude (Ho close to 90°) tells you about your position relative to the geographical position (GP) of the body • The geometric meaning of a line of position as a small segment of a large circle around the GP

💭 Think About

• When Ho is 88°45.0', how far (roughly) are you from the GP of the body in nautical miles? Think about the relationship between zenith distance (90° − Ho) and distance. • Is a normal celestial LOP a straight line, a circle, or a small part of a circle? How is it usually represented on the chart for practical plotting? • Which of the answer choices describes the standard practical plotting method used in the altitude‑intercept technique, regardless of whether Ho is high or low?

✅ Before You Answer

• Compute the zenith distance: 90°00' − 88°45.0' and interpret that as distance (NM). • Confirm how an LOP from a single sight is usually drawn on a chart in routine celestial navigation practice. • Verify whether any option suggesting a full meridian/latitude/longitude line matches the usual definition of a celestial LOP from one sight.

The line of position determined from a sight with an observed altitude (Ho) of 88°45.0' should be __________.

reduced to the meridian and plotted as a latitude line

plotted as an arc around the GP of the body

calculated as a longitude line

plotted by using an intercept from an assumed position

🔍 Key Concepts

💭 Think About

✅ Before You Answer