I’ve read that early Hawaiian navigators used this method, and I guess they came originally from Tahiti but i never studied up on this. From what little I know they were quite expert at this. What I wonder is how they knew how to find the islands of Hawaii in the first place. Little specks in a gigantic ocean.
They honed in on AM radio signals like the Japanese bombers attacking Pearl Harbor???
Knowing the time, at Greenwich, is essential to knowing the Ground Position of a sighted star.
The Polynesians probably used celestial approximations in coordination with other navigation aids such as currents, trade winds, clouds, fish, etc. They did not have the means to manufacture a modern sextant.
The Polynesians tended to explore into the wind. That way if stores started to run low they could turn and run down wind to get home.
WWG1WGA
Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)
LonePalm, le Républicain du verre cassé (The Broken Glass Republican)
I don’t know if you’ve read Hawaii by James Michener (I recently re-read it), but the way he lays it out is it the existence of the Havaikii Islands was probably a legend among the Tahitians as they would go very very far in their canoe ships (catamarans). He speculates that if they could have gotten close enough they would have seen a star in the sky right in the same place, always on the horizon, and it would have been Mt. Kilauea, because it would have been very active in that era.