Ah well, I've delayed this from yesterday.
I got my bike out of the car at 04:55, prep'ing for my commute. I looked up at the starry sky to see if Orion was visible.
I saw a bright light ( brighter than any of the stars ) travelling northward at quite a rate of knots. There were no navigation lights and the intensity of the light didn't fade as the thing passed.
It travelled half the horizon ( directly overhead to horizon ) in about 15 seconds. Visible all the way.
It was totally silent. The speed was similar to a low flying helicopter, but they make a row and their lights flash. Satellites travel West to East. This thing was travelling South to North.
There were no discernable con-trails when sunlight illuminated the sky half an hour later.
If it was high altitude, it must have been travelling at least ten times the speed of a commercial jet aircraft.
If it was low altitude, I couldn't hear any engines or rotor pulsation. Nor constant or flashing navigation lights.