“That’s pretty pokey for an interstellar object of this nature, if I recall correctly.”
They rather ingorantly failed to recognize how the asteroid is millions of miles distant from the Earth at most memnts in time until a hundred years from now, but it also closes to virtually zero distance from the Earth’s orbital path in some years as its own orbital path intersects with the Earth’s orbital path while the Earth is elsewhere along its orbital path. It just becomes a matter of time before they both happen to be at the same point of space along their respective orbital paths at the point where the intersect at the same moment in time like two commuter trains or two commuter cars arriving at the same intersection at the same time. Until the day of the fatal collision at their fated intersection they remain far apart.