I was walking on the beach near the Tybee lighthouse with a friend. I noticed a movement in my peripheral and thought I was seeing a falling star/meteorite because it was moving in a downward angle pretty quickly, in the direction of the ocean. The only thing off was the color was vivid blue, like cerulean. It was leaving a very short tail in the same color. I pointed up to it for my friend and shouted, "What is that?" But by the time she looked up (within seconds) it, and the tail it left, had completely vanished. My friend didn't see it and then yelled at me when I asked again, louder, because she didn't want to disturb anyone with it being so late. I then thought maybe it was a flare or maybe a firework, but it winked out instead of fully descending and no one else seemed to have noticed it and nothing followed in its wake. No trails of smoke were visible in a clear sky. No boats or aircraft entered the area after its appearance looking for someone who might have fired a flare. I didn't even notice a plane the entire time we were there, which was over an hour. It was pretty high up, not and out over the water, but not as far over as the boats in the distance. So I am not sure what it was. I didn't even think, "UFO," until after it was gone and I had already tried to identify it with reasonable explanations.