On 16 October evening twilight will occur at...

Question 1 of 2707066636eea28f7522a1c51ab24

On 16 October evening twilight will occur at 1746 ZT. Your DR position will be LAT 28° 43.2' N, LONG 60° 29.8' W. Considering their magnitude and location, which of the following are the three best stars to select for a fix at star time?

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Question 1 of 27070

🔍 Key Concepts

• Star selection for a 3-star fix (good azimuth spread, altitude range, and brightness) • Your assumed position latitude vs. declination of stars (circumpolar vs. low-altitude stars) • Importance of separation in bearing (ideally 60°–120° apart) to reduce position circle crossing angles

💭 Think About

• Look at each group of stars and imagine their positions in the sky for LAT 28° N: which set will give you stars spread widely around the horizon instead of clustered in one area? • Which choice avoids having most of the stars very far north (near Polaris) or very far south, and instead gives you comfortable altitudes (say 20°–70°)? • Which option provides three bright, well-known navigation stars that will likely be above the horizon at evening twilight in mid-October in the western North Atlantic?

✅ Before You Answer

• Verify which stars are near the pole (almost due north, small azimuth change) vs. which are more to the east/west/south, giving good bearing spread. • Check for stars that might be too low or too high in altitude from 28° N around evening twilight in October—extreme altitudes are less desirable for a fix. • Confirm each option’s stars are not all in the same general azimuth sector (e.g., all in the west or all in the north).