10 pale yellowish bird figures speeding silently through the clear sky

I was standing on my balcony at 5:10 am having a cigarette, looking at the stars when out of nowhere I saw what looked like a flock of birds, if I recall correctly was about 10 birdlike shapes, moving south through the sky.  There was no sound, just complete silence, and the birds or whatever they were pale yellowish in color.  They were in a bent straight line as they moved south through the night sky.  The group of pale lights “birds” did not make any sound and after about 5-7 seconds were just gone.  The sky was clear and no clouds in sight…so not sure what it was, but due to the pale glowing figures moving fast and not making a sound has me baffled.