This thread originated from an idea I had while reading JohnD's post, here, about Why Do We Have An Atmosphere?

Put simply, what if life originated on Mars, was carried to Earth via meteoric ejecta billions of years ago, and again, via intelligent, humanoidal space travel millions of years ago, perhaps when the Martians were realiziing it was only a matter of time before their planet became a dead planet? Or perhaps they were merely branching out, doing what we're doing as we're planning our Martian trips.

Regardless, (and here's the spooky part), what if the Chicxulub Crater was the result of an intentionally caused impact as part of a Martian-forming process???