On 3 February your 0550 zone time DR position is LAT 26°16.0' N, LONG 112°05.0' W. Considering their magnitude, azimuth, and altitude, which group includes the three bodies best suited for a fix at star time?
• Star time sights and why you generally prefer 3 widely spaced bodies around twilight • How altitude (Hs/Ho) affects the quality of a fix (too high vs too low angles) • Importance of having good azimuth spread (separation around the horizon) between bodies
• Look at the date, time, and latitude: which bodies are likely to be high in the sky and which closer to the horizon? • For a 3‑body fix, how should the bodies be spaced around the compass—clustered in one quadrant, or spread out? • What happens to the reliability of an LOP when the body is very close to the zenith or very low near the horizon?
• Make sure the chosen trio is not all in nearly the same direction (poor azimuth spread) • Avoid bodies that would likely be very high (near 90°) or very low (<15°) in altitude at that time and latitude • Confirm that the set includes at least one bright star/planet well separated in bearing from the others for a strong fix geometry
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