Last night we saw Christmas ships on the Columbia River, an annual phenomenon, largely governed by radio waves, by which I mean: we were tuned in to the shared frequencies the Coast Guard uses, with others, to ensure safe operations in the water ways (for example, in this case we had an oncoming tug-pushed-barge plus a stern wheeler (both would require bridge swings (the railroad bridge is quite low (the I-5 bridge is the last draw on the USA I-net they tell me)))).
Christmas ships are thematically lighted, mostly privately owned watercraft, used at night this dark time of the year, for purposes of pageantry and celebration -- this night under a full moon.