Chain formation of objects at very high altitude and speed, changing to cluster formation as they moved.At 20:30 my girlfriend and I went outside to observe an Iridium flare, it showed up right on time and was bright, about magnitude -8. An hour later, I went outside to go to the grocery store. I passed the spot from where we observed the flare, stopped, and looked up. I saw a straight line of about 5-7 dimly lit objects moving through the sky, first appearing at about altitude 30 degrees and azimuth 6 degrees. It appeared to me that the objects did not emit light on their own but were reflecting light from the sun below the horizon. They moved about twice the speed of the satellite we had seen earlier. There seemed to be a bit of haze surrounding the group. They were almost pinpoint sized objects, dim yellow color (which makes me think it was reflected sunlight) and as they approached about azimuth 0 degrees, they changed formation from a straight line to a cluster. The rearmost objects caught up with the foremost objects to make this cluster. As the group continued across the sky, they disappeared at about azimuth 310, which appeared to me that the objects moved into the shadow of the Earth and could no longer be seen. The objects made no sound and seemed to be very high above the Earth and moving at incredible speed. As a background on myself, I am an RN and budding amateur astronomer.