Here's a bit of geology about which I was unaware before I saw this
video:

<https://www.youtube.com/watch?v=KAR4fAX5T7Y>

Short version: According to the video, there are a number of
elliptical depressions of various sizes throughout the Carolinas and
DelMarVa region and Nebraska and Kansas. The major axes of these
ellipses approximately converge around Saginaw Bay, Wisconsin. The
video's hypothesis is they are a consequence of Laurentide glacial ice
boulders created as secondary ejecta from an extraterrestrial impact
on the Laurentide ice sheet at or near present day Saginaw.

This Wikipedia article says there are a number of similar elliptical depressions throughout southern USA:

<https://en.wikipedia.org/wiki/Carolina_bays>

These additional "bays" are consistent with the video's hypothesis, in
that ejecta should form a circular arc centered around a point. The
hypothesis would predict no "bays" in other directions, as any ejecta
elsewhere would have fallen back onto the Laurentide Ice Sheet,
leaving no trace once it melted.

However, the Wiki article doesn't mention the major axis orientation
of these additional "bays". Instead, it suggests the consensus is the
origins of these bays are of strictly terrestrial origin.

If these "bays" are of impact origin, their elliptical nature
intrigues me. My understanding is impact craters of extraterrestrial
origin are almost always circular, as they are a consequence of a
bolide exploding from the shock of a high-speed impact. However,
secondary ejecta from a primary extraterrestrial impact would have substantially less velocity, and so would create an elliptical crater
that preserves its entry orientation. Also, as the secondary ejecta
of such an impact would be ice of terrestrial origin, the "bays" would
not contain extraterrestrial material.

--
You're entitled to your own opinions.
You're not entitled to your own facts.

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