The origin of the universe for an upcoming story I have planned hinges around an idea where, when the asteroid that killed the dinosaurs hit Earth, instead of wiping out the dinosaurs, it opened up a portal that deposited them in another part of the galaxy. Now, this is of course most assuredly something that could never happen, but is there any way I could create a scientific explanation that would at least sound halfway good? One idea of mine is that, somehow, a wormhole briefly develops inside of the asteroid right before striking the Earth. As it hits, it sucks in large amounts of life, but then closes fast enough that the bulk of the biosphere is left intact. Another is that a miniature worm hole flying through space is ever so slightly pushed off course by the asteroid, swallows the asteroid, then rips its way through Earth at such a speed that, once again, lots of life is sucked through but the Earth is left intact. Again, I know that none of this could happen, but I'm looking for something that sounds pretty and scientific. I might resort to supernatural stuff like alien sorcerers, but I want to try for a more naturalistic explanation first. Any thoughts on how I could make this work?