Oh dear me... Doomed.

Well the fact is that yes we are all going to die. What is it that you see as a direct threat to humanities existence here on planet Earth and, when is this most likely to Begin happening? Hay the 10th of March is just a couple of weeks away.
We obviously differ on the risk to humanity that the galactic plain might have to life on Earth. Or you are just pocking a stick at it. . . ..
I see that a group of astro-buffs have worked out that Hypotheses is going to get mighty close in the year 2036. Mighty close could just as easily be a miss.
Is this the extinction event you are talking of. No probably not. The fact that a ever larger group of astronomers are constantly scanning the near to earth objects looking for the sort of thing you seem to be so worried about. With ever improving equipment we are looking for that rouge object.
I will at this point voice a concern, When a object is drawn close to the sun as comets are. Would it not be normal enough for their track to be Alard by the slingshot of solar gravity. Could this change be calculated to give us the best chance of deflection before that occurs, If it were shown to be a possible risk object. Do we stay lucky.
Just by miss quoting what you did not hear can a panic button be pressed. Like. . . These larger than 40km objects are rare and few are actually Earth crossing object. One in a million year event is of some concern when its been five million since the last one.. but.
None of this is revalent as none of this is even any where likely to happen. ever. or tomorrow.