There has been few more of them around the world.
> Saturn's hexagon is a persisting hexagonal cloud pattern around the north pole of the planet Saturn, located at about 78°N.[1][2][3] The sides of the hexagon are about 14,500 km (9,000 mi) long,[4][5][6][7] which is more than the diameter of Earth[8] (about 12,700 km (7,900 mi).
They even added the fog (the fog in the picture is white and while there is dust on mars it's rather brown as the planet's surface https://mars.nasa.gov/imgs/mep/weather/PIA22520-600.jpg ).
Just kidding around really, but I have to imagine that pockets of circular water currents like this, are more common than we would think.
We just can’t easily observe the dynamics of water flow until something like this happens, where a bunch of ice builds up and makes it obvious.
Vortices in a near-2d-flow like a river will absolutely be circular, vortices need to be coherent in some plane in order to sustain themselves.
The specific circumstances here must be that that the water is on the edge of freezing during downstream flow and there is a naturally-very-long-lived vortex in one region for it to initially form the ice-disc. Must also be followed by some very-gently-bounceing-off-the-edges, and the river never getting too thin for it to get stuck.
Well, no: https://ourplnt.com/earth-smooth-billiard-ball/
The myth is springs from the fact that if you had a smooth earth with a radius of center to Mariana Trench, and another smooth earth with a radius of center to Mt. Everest, you could shrink both of them by the same factor and fall within allowed billiard ball specifications. That says nothing about smoothness, only about the allowed size of ball.
If you actually shrunk the earth we're living on, the ball would still be rejected as quite too rough.
What's different about the modern day is that there are 1. way more people to look, 2. way more cameras to record, 3. the internet to disseminate any unusual thing widely.
This particular hypothesis seems to be invalidated by the fact that the phenomenon was observed before, back in 1895. See the wikipedia link in comment above.
> I agree in part in that I am skeptical that full self-driving cars will happen in the next few years, but he is completely wrong when it comes to the long term. Not only will the tech get as good as humans, but most forget to account for the fact that the environment will meet the cars part way. [..]
As you can see, speculation is well accepted in the HN community. This is why I think spritecranberry's comment was unfair.
Full thread here: https://news.ycombinator.com/item?id=22085756
>large-scale issues
Oh, so since this is an isolated phenomenon that it is your preference to ignore this as evidence for your cause because it doesn't meet your criteria. That's not science either.
>This sort of speculation harms the argument for climate change more than it helps it.
What? Do you get mad at people for saying "it looks like rain"?