I remember a StackOverflow question about a one-ton tungsten(?) ball heading towards Earth from the edge of the solar system, I forget how many nines after the

I remember a StackOverflow question about a one-ton tungsten(?) ball heading towards Earth from the edge of the solar system, I forget how many nines after the decimal point in it's velocity. The question was what what would happen to Earth--and the very surprising answer was basically nothing. The ball would be vaporized very quickly by the interplanetary medium and disperse long before reaching Earth. Some of the energy would hit but it wouldn't be enough to notice.