Celestial navigation, the combined art and science of finding one's way about the ocean by using measurements of celestial bodies, seems a perfect field for astronomers who go to sea, or sailors of scientific background. In fact almost no astronomers have any background in the practice, and nothing that an astronomer would recognize as real science is required to wield a sextant. Anyway, everyone uses GPS nowadays.
But, hold on. There is something more here, something really worth explaining and looking at.
Under construction; to be continued