Cool game, thank you.
Perhaps it would be more clear to make the bright time of day after the rocks switch a little longer to be able to orient. The animation of waves crashing on the rocks is a critical addition - the game would have been irritating without it.
It's also fantastic that you put options for the ship speed and beam width. It would be great to include a setting for the screen brightness too.
I got in a few situations where the large ship was bouncing off rocks from the left and the right. I think it was around 30 bumps - can a ship sink? I think it's just keeping track of the bumps - as far as I can see there are no bad consequences... I don't think a ship can go backwards even though that is a natural reaction (and they can go backwards in real life). Is it worth adding? Maybe if the bumps have an impact on the score.
"The largest ship comes home last. It always does."<== No, it didn't in the game! :P
Good luck!