I was walking west on the high line canal trail, just east of broadway. for some reason i looked above me and slightly behind, where i saw a basketball-sized metallic sphere flying just above treeline and within about 4 feet of a canadian goose; both were heading west at about 35 mph, though their trajectories differed by about 5 degrees. at first i thought the object was an rc helicopter, but then i realized it had no propeller, no wings, no stabilizers, nothing–just a sphere. with this realization, i stared at it, and watched as it (and the goose) flew due west overhead (at that point following the trail) and across broadway. there was traffic and i hoped that others saw what i was seeing. i lost sight of it as i watched it for another 15-30 seconds as it disappeared from my view. to me, my reactions were more remarkable than the actual sighting. initially i was disappointed, as i would have liked to see something more interesting than a metallic sphere that flew without changing course. that feeling only lasted a few seconds before the entire incident was "pushed" out of my thoughts; as if part of me didn't want to remember what had just happened–at all. i continued experiencing this "lacunar amnesia" for over a year before i could even tell my wife about the incident, and then only with great effort, and nearly two years to make this report.