On 16 July your 1920 ZT DR position is LAT...

Question 1 of 2707066636eea28f7522a1c51ab17

On 16 July your 1920 ZT DR position is LAT 25° 36.0' N, LONG 172° 18.9' W. Considering their magnitude, azimuth, and altitude, which group includes the three bodies best suited for a fix at star time?

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Question 1 of 27070

🔍 Key Concepts

• Star selection for a three‑body fix (good spread in azimuth, similar altitudes) • Ideal altitude range for navigation sights (too high or too low is less accurate) • Effect of brightness/magnitude and using a reliable mix of stars vs. planets

💭 Think About

• From your DR position (25° N, 172° W in July, evening), which bodies are likely to be reasonably high above the horizon (not near zenith or scraping the horizon)? • Which choice gives you three bodies that are all bright AND spread around the sky (roughly 90°–120° apart in bearing), rather than all lumped in one part of the sky? • Are any of the options dominated by planets that might be very low or very high at that date/time, compared with well‑placed bright stars?

✅ Before You Answer

• Check for good azimuth spread: avoid groups where two or three bodies lie in nearly the same direction. • Check altitude suitability: favor bodies that would likely be between about 20° and 70° altitude from 25° N in July at evening twilight. • Check reliability/brightness: prefer bright, well‑known stars, and avoid combinations where a body is likely to be too dim or poorly placed for a precise fix.