Right, so this is the kind of report that genuinely gives me goosebumps because I've had almost the exact same experience over Salford back in 2019. Massive, slow, completely silent - that last bit is always what gets people because your brain just refuses to accept something that size making zero sound.
What struck me about your account is the sheer scale of it. That's not a drone, not a conventional aircraft, nothing man-made moves like that at low altitude without any engine noise whatsoever.
A few things I'd ask - did it have any lighting at all, even faint? Did your dog or any animals nearby react? And roughly what time was this, because there have been clusters of similar reports across the north of England over the past 18 months that I've been tracking.
This deserves a proper writeup if you can remember any more details. The more specific the better, shapes, any colour variations in the surface, how long it took to cross your field of view. Get it all down while its fresh in your memory, that stuff fades faster than you'd think.