On 20 June your 1742 zone time DR position...

Question 1 of 2707066636eea28f7522a1c51ac3f

On 20 June your 1742 zone time DR position is LAT 24°55.0' S, LONG 8°19.6' E. Considering their magnitude, azimuth, and altitude, which three stars are best suited for a fix at star time?

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Question 1 of 27070

On 20 June your 1742 zone time DR position is LAT 24°55.0' S, LONG 8°19.6' E. Considering their magnitude, azimuth, and altitude, which three stars are best suited for a fix at star time?

🔍 Key Concepts

• Star selection for fixes – brightness (magnitude), spacing around LOP intersection, and altitude limits (not too high, not too low) • Observer’s latitude and star declination – which stars are well placed for a southern mid‑latitude observer (~25° S) at local evening nautical twilight in June • Azimuth spread – choosing stars that give good crossing angles (ideally 60°–120° apart) rather than being in a line

💭 Think About

• From 24°55' S, which stars listed are even likely to be visible and well above the horizon in June evenings? Think about which are far north vs far south. • Which set of three gives you a wide spread of azimuths around the horizon instead of clustering in one part of the sky? Picture where each choice would lie (east/west/south/north). • For each option, ask yourself: Are any of these stars likely to be so high (near the zenith) or so low (near the horizon) that they’d make poor sights for a fix?

✅ Before You Answer

• Check declination and approximate RA (right ascension) of each named star to see if it is favorably placed for 20 June at this longitude and latitude. • Verify that each of the three chosen stars in a set would have an altitude between about 15° and 75° at the time of observation. • Ensure the three stars have good azimuth separation (roughly 60°–120° between them) rather than lying nearly on the same bearing.