Confirmed NOT ISS (was below horizon then); confirmed NOT airplane (checked FlightAware).
No haze in the sky (this was from Marin County). Other stars and moon were crystal sharp, yet this was very blurry/hazy glow, so at first, before I could tell how fast it was moving, I thought it was a comet, before immediately checking myself that (a) no comets are scheduled now; (b) that would be an insanely bright comet; (c) it had no tail which would be expected of such a bright comet.
But then it disappeared rapidly over a period of several seconds as it dipped into the Earth's shadow (similar to how the ISS would vanish after sunset, too).
A friend (literal actual rocket scientist) said perhaps it was the X-37 returning; but I can't see any record of a recent return since OTV-6 in Nov 2022.
Anybody?
