What this emphasizes is that any relatively small object that tracks an orbit conforming to that of Earth itself and close enough at hand is a prime candidate for an impact however distant that may be. Worse though that same object is been constantly disturbed in ways that make orbital prediction almost impossible.
It is not well understood that we need to monitor our own satelites constantly to ensure they do not get lost and that is almost an easy problem. Thus these objects all need to be located and placed inside a probability equation that needs to be updated every century or so.
It will be quite a while yet before we are able to properly do this although it generally entails putting out sensing platforms to scan the space all along Earth Orbit. This will identify those in the window. It will not easily identify erratics coming in from the Kuiper belt but may also be helpful in that as well.
We really need a full space station at both Lagrange Points on Earth's orbit.
Russian scientist spies mountain-sized asteroid heading our way
In the film, Lipunov says it's difficult to calculate the orbit of big objects like 2014 UR116 because, as they hurtle through the solar system, their trajectories are constantly being altered by the gravitational pull of nearby planets. "We need to permanently track this asteroid, because even a small mistake in calculations could have serious consequences," he said.