A month or two at sea with no outside communications will make a believer out of anyone.
I have sailed (short trip) from Oahu (Pearl Harbor Marina) to Molokai in a non-powered (i.e. no motor, no electricity) Sail boat. We were becalmed at night. No human light within a few miles. The Stars were overwhelming, but to stand to try to find the horizon was totally disorienting.
Bio-luminescence is a thing to behold when you are far enough from shore in a calm sea.
Look up, you see stars.
Look at the horizon, you see stars.
Look DOWN, you see stars (actually, plankton)