Rectangular object moving at a very high rate of speed with no noise.

While playing outside in the snow on a cloudless sky evening at around 7PM a friend and I say a single rectangular object with 4 lights that appeared to be at the corners moving at a very high rate of speed across the sky from north to south. The craft was at a very high altitude and no noise was heard. 
We were both laying on the ground on our backs in the snow.  I saw the object and did not say anything.  As the object moved off my friend than said to me "Did you see that?"  I said ya what was it. 
We both didn't know but concluded it was moving too fast to be an aircraft.  We were both aircraft entusiasts built alot of model airplanes and lived near the Wilkes Barre Scranton airport so we felt we had enough knowledge to make that conclusion. 
The craft moved extremely fast, not totally unblievable speed but alot faster than any jet.
As I grow older I think back on that night and with the increased knowledge I feel the object may have been the SR-71.
Witness indicates that the date of the event is approximate.  It's unlikely that an SR-71 could be seen, but not heard.  They are very loud, particularly at the high power settings which are necessary for that aircraft to achieve high speed.  PD