large blue light with no sound; was unable to move

Time between 9PM & midnight.  Walking home late with hubby and suddenly noticed a very large blue light in the sky.  It seemed very low, perhaps just because of the size.  A fist held at arm's length would just about contain it.  It crossed our path on a diagonal, moving very slowly.  It continued (as best I am aware of) without any pauses.
I stopped just because it caught my attention.  My mind raced to explain what I was seeing.  The best I've been able to come up with is a helicopter with an all-glass front that was illuminated so brightly from within that nothing was visible except the light.
But this doesn't explain the hardest part to comprehend.  It made absolutely no sound whatsoever.
I'm not sure of how long I stood there frozen in my tracks.  I could not move.  I was scared and wanted to run, but I could not move.
Next, I was walking (not running) home again.  The last I saw it, it was directly overhead.  I did not turn back to see it once I could move again (which makes no sense to me at all).  I had no fear of "it" following me.  I fully remembered all of what I've written here; there was no amnesia of seeing this light.  The moon doesn't move that quickly across the sky and the fluidity of the movement (in my opinion) rules out anything like "swamp gas." ~~~~~~~~ I saw another light in the late 70s in Virginia; it was green, smaller, and higher in altitude.
And in '76 or '77, a metallic object that was NOT shiny.  Sort of a rust color.  Could be termed cigar-shaped, or could be a disc seen at such an angle that it appeared elongated.  This was near Pittsburgh, PA.
Date is approximate.  Illustration by witness did not survive the transfer to the database.  PD