Interesting that an apparently major impact event was caught by amateurs and not studied in real time as Shoemaker-Levy was.
I take it that this meteor was an unknown entity? Kind of out of the blue? Any notion being put forth as to size? A whole lot of discomfiting unknowns here, imho.
Yes, absolutely unknown and not seen until someone caught the actual impact on film. That argues for a dark object that was not reflecting much light before the impact; i.e., it wasn't a comet, but most likely a meteor.