[don1reed]

The best way to learn the navigational stars is to first learn to recognize the shape of the constellations wherein they reside (Zodiac names).

If you have a clear sky from your own back yard tonight, have a go at it. After a bit it will become routine. There are countless books, magazines, star charts available both hard copies and online to get you started.

At sea, wx, fog, haze, rain, industrial smog, and clouds will block them from your view when you need them the most. The only exception is the sun which when sitting behind a cloud will present itself as a fuzzy cotton ball sometimes. And, even then it is usable if you use the center of mass as your target and use the center of the sun for your calculations rather than upper or lower limb.