I've posted before here on the hypothesis that there was an impact over North America 12,900 years ago, as this has been made public in abstracts and now papers. The link is to an article that says this and claims of more recent impacts is exaggerated. It's kind of interesting on how science works. It's interesting to me as I have been co-author with Pinter a couple of times on other stuff (Santa Cruz Island California stuff), and with Kennett, who is part of the 12,900 impact group, on other things.
some quotes from article: "Carl
Sagan once said that “extraordinary claims require extraordinary
evidence”; we argue that these impacts do not meet
that standard."
This applied to earthquake predictions also, I suppose.

"We suggest that these Holocene features
are clearly eolian, and that the term “chevron” should be purged
from the impact-related literature."

Another scientist I know suggested that Pinter is correct on using these coastal features as evidence for impacts is weak at best.

"The National Science
Foundation now emphasizes “transformative” research, and few
events are as transformative as an impact. In an era when evolution,
geologic deep time, and global warming are under assault,
this type of “science by press release” and spectacular stories to
explain unspectacular evidence consume the finite commodity of
scientific credibility."

I think that the 12,900 impact hypothesis is correct in that there seems to be pretty strong evidence for it now, and I don't buy the argument that the extra-terrestrial component is just raining continuously from space. I'm not saying every detail is correct: perhaps it is weak for the Carolina Bays (I don't know).

I'll keep an eye on this as it plays out over the years.
Chris

• Pinter abd Ishman, GSA Today, impacts