My sister and I saw a massive, silent, v-shaped formation of bright white lights fly directly overhead.

On a cool summer night, I arrived home after dark to find my sister and mother star gazing on a swing they had dragged to the middle of our back yard.  My mother got up and walked over to greet me remarking about how clear it was and how beautiful the stars were.  She told me she was going in because it was cold and that I could take her seat.  I sat next to my sister and we both were looking straight up gazing at the stars.  
I was about to get up to go inside when I looked straight at the horizon.  Suddenly, I noticed what I can only describe as a v-shaped formation of white lights coming at us from over the horizon.  They looked the way jets flying in a v-formation would.  The white lights were brighter than the stars that filled the background.  I would say that there were 11 lights in all with 5 on each side and one at the tip of the formation.
My heart immediately jumped and I yelled for my sister to look as I extended my arm and pointed at the lights.  She quickly looked as the lights continued toward us.  They shot directly overhead at incredible speed.  
There was no noise what-so-ever coming from the object(s) before, during, or after the event.  I remember,  distinctly, that as the lights passed directly overhead, they seemed to be distorting the sky as if they were connected to a "v" or boomerang shaped object - A black object with white "headlights" moving swiftly across a clear, black, star-filled sky.  I assume that the object(s) was flying relatively low because the formation of the lights spread out as it passed over us.  I would estimate the object to be extremely large considering the amount of sky it spanned across- (perhaps 1000 ft. from tip to tip).  My sister and I had no explanation for what we saw.  I am quite positive that it was not a natural event because the lights were spaced evenly apart and did not waiver from their position in the "v" at all.
Witness indicates that date of the event is approximate.  PD