Between 2010 and 2012, maybe. mayport, fl. late at night. past 2200. look up at night sky, see part of sky looks odd. triangular in shape, black, but different from the sky. single white light, steady, at each of the corners. moved too slowly to be any aircraft i've ever seen, even at a terribly high altitude. if it was terribly high, then it must have been a few football fields from tip to tip. if it was lower, in the range of a plane during takeoff, it would have been regular, maybe even smaller than normal commercial aircraft. difficult to tell, as was a rather dark night. was maybe spring or fall…Comfortable time of year. apologies no better details, long time ago. saw on discovery channel that other people have seen triangular things that "float". this thing moved far too slowly to be anything i had or have ever seen since. i spoke with another sailor who was topside with me, pointed it out to him/her. i can't even recall who it was, but he/she did see it, as well, so i was not imagining it.