By non zero you mean effectively zero though. Those kinds of impacts happened early in the history of the solar system. They’re not impossible, as there are sti

By non zero you mean effectively zero though. Those kinds of impacts happened early in the history of the solar system. They’re not impossible, as there are still objects that size out there, but something would have to sling them towards the Sun. Arguably were most at risk only during the next few centuries. After that our space capabilities will probably make us nearly immune to fast moving rocks from space.