An object that was higher than a plane that moved slowly and could stop for a duration of at least five minutes.

Around one o'clock today I noticed a cylindrical object in the sky that was moving to slowly and far too high in the sky to be an airplane. At first I thought this object was "twinkling" because the surface seemed to be a mylar type of material and it was reflecting the sun but after I watched it for a moment it established a clear pattern of blinking on and off, a slow one. It slowly moved across the sky until it was directly above me and it stopped for about five minutes, directly where the sun would be at noon. I was on the phone with my friend so I hung up to take a video. 
After unsuccessfully trying to get a video, it was just too small, I called my downstairs neighbor and she came up to see it for herself. (While I was trying to get video it had started moving and then stopped again when my neighbor came out to see it. It had moved further south and a little bit east of the noonish sun before it stopped again.) She observed it and was just as clueless as I was as to what it was. We chatted for a bit and the next time I looked up it had moved on. 
This thing never stopped binking but the blinking did slow down. When it moved it stayed at a very slow pace, far too slow to be a plan. When it stopped, it stopped, it did not move at all from that spot. It was shiny, the color of a mylar balloon. I've seen weather ballons, this was not it. One more thing, my mom worked for NASA and DARPA, I am not easily fooled, this was strange.