Some navigational stars are only moderately bright although they are in the top 20 brightest stars. Antare and Fomalhaut are two such stars. They are used for navigation from September to November but are not easy to identify among their nearly as bright neighbours. The method for indentifying them is to relate them to brighter neighbours which have been identified in previous periods of the year.
(GPS navigation cannot be relied on during periods of uncertainty. Traditional methods of navigation is still a necessay skill.)
Using an identifying map.
Knowing the date or even only the month of a star help locating parts of the sky where it may be found.The map giving distances and angles to its more distinctive neighbours then help its identification.
Figure 1: Antare in Scorpii with its neighbours. The centering mark is the Southern Celestial pole.
Figure 2: Fomalhaut with Alpha, Beta Grus…
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