I was on my deck in my back yard with my spouse. I observed to my NW an object that I believed to be a balloon floating. Random party balloons floating by is not too uncommon to see on holidays around here. I would check its progress to see wind direction every 20-30 seconds or so. I noticed it had not moved. I oriented the object to a tree in my back yard to see if it was moving at all. I then noticed a flicker of light emanating from it. My initial thought was that it was a mylar balloon and it was reflecting light from the shiny side of the balloon as it gently rotated towards and then away from the setting sun. Again, I thought it odd it had not moved left or right or appeared to get closer or farther away. I asked my wife to retrieve my binoculars. Once I had them I reacquired the object and observed a dark pod like object with a brilliant pulsating aqua blue strobe light to one side of the craft. I observed the object for nearly 20-30 seconds and then gave the binoculars to my wife. When I went to point it out her again so she could orient the binoculars it was gone. It did not move and from the time I observed it till the time it we lost sight of it. My wife is near sighted and never saw it. Very frustrating.I believed it to be approximately 50 degrees above the horizon and at an altitude that we often see low flying craft such as helicopters and small planes. It was hard to gauge distance but I would guess 4-6 miles away. The sky was still very blue for being later in the day and no clouds to speak of. It was a beautiful sky for Fathers Day.That was no balloon...it was a solid craft. Thank you for your time.