slow moving dark craft near tappan zee bridge in nyDate & Time of sighting: Friday morning, October 23, 2015 at approximately 11:25 am.Place observed: From my car as I was driving from Rockland County NY, on I-287 East in South Nyack, NY approaching the Tappan Zee Bridge. The object was just south of the bridge, heading northeast, slowly. It was rather low, at approximately a 40-degree angle from my location and large enough to be seen from the approach to the bridge on the Rockland county side of the Hudson River. The object was neither over the bridge nor the Hudson River but was overland on the Westchester county side of the river, just south of the bridge. The bridge is just over 3 miles long so the object was at least that far away from me at the time my girlfriend and I first noticed it out of the windshield of the car.As the road curves a bit the craft was on the left side of the car (south of the bridge) for most of the observation.Description: Rectangular and black. Though not a perfect rectangle. More cigar shaped but it was not round like a cigar. Slow moving, angling down like it was preparing to land. It was large, not huge, about the size of a large commercial or military jet, but much darker than the gray used by the USAF. Most striking was its slow speed and shape. Flight characteristics were more like a blimp then an airplane. If it was a blimp it is one I’ve not seen before.The object was visible to us as we drove almost the entire length of the bridge. We were driving in well moving traffic, moving at highway speeds for almost the entire length of the bridge. We lost sight of the craft as we approached the Toll plaza and just after we cleared the suspension portion (superstructure) of the bridge. At that point, it was too low from our angle to see anymore and was now to north of the bridge.My girlfriend attempted to record the object on an iPhone but she did not begin recording until we were already passing thru the suspension portion of the bridge and since the craft was now at a low angle (approx. 10 to 15-degrees), she was recording it as we were passing thru the beams / cross section of the superstructure of the bridge. Therefore, the recording is basically a series of beams passing by at highway speed but the craft was visible to the eye in-between the breaks in the beams. Unfortunately we waited too long to begin recording. The reason for this is at first we assumed it was a slow moving large airplane moving away from us. However, the more we observed it and had time to discuss it, we realized what we were observing was unusual and worth trying to record. If there had been no traffic on the bridge, I would have stopped and gotten out of the car to witness it longer – it was that unusual.Duration of observation – approximately 5 minutes.Conditions: Bright, clear and sunny. A beautiful day. Perfect conditions for observing the sky. And this dark, slow moving object was perfectly visible and stood out quite vividly.Feeling – an odd aircraft that neither of us could identify. It did not look extra-worldly or intimidating in anyway just out of the ordinary.