Spherical object moving rapidly across the sky at Plum Island State Park MASunday March 8th 2009.I was at Plum Island State Park in Massachusetts with my wife on a fairly warm day for the time of year, and we had decided to take a blanket and lay on the beach to have some lunch. After eating, we laid down on the blanket and found ourselves looking up at the sky discussing the airplane contrails we were seeing all over the sky.From our left (which was north) there appeared to be a ball shaped object (not a disk, but spherical shaped) travelling at great speed and directly overhead. It crossed our field of vision in about 10 seconds and then stopped suddenly at which time it appeared to simply hover and then disappeared to our right which would have been to the south. The shape was a two tone color, being a copper color on the bottom and silver metallic color on the top.There were no protruding features such as wings or a tail – simply round and featureless apart from the color.We both stood up and watched it saying ‘what the heck is that?’ I am a private pilot and this was certainly not a plane or a bird. It was difficult to estimate its altitude but there was no contrail and it appeared to be perhaps 1000 to 5000 feet above the ocean.