...I am amazed at Your COMPLETE lack of understanding of physics. The asteroid that killed the dinosaurs was only at most a few kilometers wide and long. No where near enough to naturally become spherical. If something large enough and massive enough to achieve this hit the earth in real life...you be lucky to live through it period. Something that big would not leave a crater. it sterilize all surface life. Last time something that big collided...was over 700 million years ago. Life will only survive that because life will survive underground as its not massive enough to leave anything more than a rather large hole in the crust...as in the lava seen from the impact is you looking directly at the mantle lava. And that's even bigger than something just capable of spherical shape. You would see a object like that Centuries before it hit. Without telescopes. And if it came in quick enough for it not to be noticed...it's even worse, as when measuring impact energies, velocity is a squared variable, while mass is a linear variable. And for a celestial body to be missed before impact when it has the mass(no...there is no material with enough mass for it to not be seen before impact that wouldnt have just flung the earth out of its orbit...if it didn't just sterilize the earth completely, and of course...black holes can't be seen)it has to be going very quickly. The energy would quickly approach crack the earth in half speeds...which ironically would not be enough to kill life, as if a bit of landmass survives intact enough, by the time the resulting mess recollects, life might reseed the planet all together if lucky. But...all the math leads non the less to human extinction.
Easily the most original finale I've ever seen.
