@Kalopin,
As Parados has pointed out, fossilized dinosaur bones have been found on every continent (except, of course, Antarctica, which was an oversight on his part; that doesn't mean that there aren't any there). So your "near miss" must necessarily have wiped out life on the entire planet. You still haven't addressed the question of the origins of hmanity. If you are claiming that they arrived as some kind of "ancient astronauts," and within the last 12,900 years, then you'll need to cobble together some evidence for that, too. You'll also need to account for the literally thousands of archaeological finds of the remains of h.s.s. which are far older than 12,900 years. Then you'll need to account for all the life forms for which we have archaeological and fossil evidence which are far older than 12,900 years. It's a toss-up who is the more goofy, you or Velikovsky.