I live on the 35th floor in downtown Manhattan. Around 10:30PM was watching TV when I turned and saw what I originally thought would be a blimp with advertising as is usually seen. Instead I saw a strange object on the Hudson River (how long it had been there I don't know because I was not facing my terrace window). It was bugging me that I couldn't figure out what it was so I grabbed my binoculars and went out on the terrace. What originally looked round was now a saucer - a flat-like disc and I could only see the underside but it was slim. It was proceeding slowly toward the Empire State Building and taking its time as if on a sight-seeing trip. No other passenger planes were in the area but it appears that a couple of very small planes passed by but at a higher altitude. I expected a lot of activity once the City realized what they were seeing but nothing untoward occurred. The entire thing was lit up brightly and I could see things like doors or outlines of doors on the underside. It had lights and a large red flashing light was the most prominent. I would say it was probably the size of a passenger plane but circular. Watched for over a half hour and when it went on a straight path toward the 59th Street bridge and the East River. I thought it was heading toward LaGuardia or JFK Airport but it passed out over into Long Island. The last I observed it, it was a small dot wayout there. I thought for sure the towers at Kennedy would pick it up. When I woke this morning, there was no news of a sighting on TV. I've lived here for 35 years and have never witnessed an object like that before. How can something like that pass over a city the size of New York and nobody else saw it? It baffles the mind.