Starship Asterisk*

APOD Robot wrote: ↑Mon Feb 01, 2021 5:13 am Each ice crystal acts like a miniature lens.

hanche wrote: ↑Mon Feb 01, 2021 8:34 am Just a quick correction to my statement that we don't have rabbits in Scandinavia (I should have said the Scandinavian peninsula, i.e., Sweden and Norway): We do, but only in the far south, mostly in southern Sweden. But Östersund is about the same latitude as Trondheim, where I live. There definitely aren't any rabbits around here. But hares are plentiful.

De58te wrote: ↑Mon Feb 01, 2021 11:29 am Hmm, I wonder why if those ice crystals all form the similar identical shape for this phenomenon to happen, then why do the closely related cousin, the snowflake, all form different shapes? It is said no two snowflakes are identical.

VictorBorun wrote: ↑Mon Feb 01, 2021 8:25 am In the pic the hole in the halo ring is 12 times the disk. Therefore the radius of the ring is about 6°.
But they say the angle of deviation after entering a face of hexagon ice prism and exiting the next to the next face is 21.54° (red) to 22.37° (blue) at minimum and 50° at maximum.
I think there is a near halo that saturates the sensor's pixels so much that we see a large white disk.

hanche wrote: ↑Mon Feb 01, 2021 8:24 am
Lovely picture. But this being Sweden, I think the tracks are from a hare, not a rabbit.

We don't have rabbits in the wild in Scandinavia (I live in Norway myself.

https://www.spacecentre.nz/resources/faq/spaceflight/moon-hoax/shadows-parallel.html wrote:

Converging shadows on the Moon (as highlighted here by red lines).

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Why aren't shadows parallel in the Moon photos?

<<Some photographs taken during the Moon landings show shadows that are converging (as highlighted here by red lines).

Conspiracy theorists argue that, since light rays from the sun are parallel, any shadows cast by the Sun should also be parallel. Shadows that are not parallel are said to be caused by studio lighting, either by a light source which is relatively close and/or by multiple light sources.>>

johnnydeep wrote: ↑Mon Feb 01, 2021 4:26 pm My questions are in which direction were the two hares/rabbits going - to the trees or from them? And how close in time were their paths?

EDIT: actually I can now see that one path was from one of the trees and one path was toward the other one. And I guess it could even have been the same rabbit/hare!

orin stepanek wrote: ↑Mon Feb 01, 2021 5:25 pm

johnnydeep wrote: ↑Mon Feb 01, 2021 4:26 pm
My questions are in which direction were the two hares/rabbits going - to the trees or from them? And how close in time were their paths?

EDIT: actually I can now see that one path was from one of the trees and one path was toward the other one. And I guess it could even have been the same rabbit/hare!

Big feet probably a Jackrabbit--Hare went to trees on right & came back from trees on Left! Or it could be different ones!

https://en.wikipedia.org/wiki/Lotka%E2%80%93Volterra_equations wrote:
<<The Lotka–Volterra equations, also known as the predator–prey equations, are a pair of first-order nonlinear differential equations, frequently used to describe the dynamics of biological systems in which two species interact, one as a predator and the other as prey. The populations change through time according to the pair of equations:

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where:

• x is the number of prey (for example, rabbits);
  y is the number of some predator (for example, foxes);
  t represents time;
  α, β, γ, δ are positive real parameters describing the interaction of the two species.

The Lotka–Volterra system of equations is an example of a Kolmogorov model, which is a more general framework that can model the dynamics of ecological systems with predator–prey interactions, competition, disease, and mutualism. The Lotka–Volterra models have been used to explain the dynamics of natural populations of predators and prey, such as the lynx and snowshoe hare data of the Hudson's Bay Company and the moose and wolf populations in Isle Royale National Park.>>

neufer wrote: ↑Mon Feb 01, 2021 6:54 pm

Snowshoe hare tracks.

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Snowshoe hare tracks across the Sun & their lynx to an 11yr cycle.

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Numbers of snowshoe hare (yellow, background) and Canada lynx (black line, foreground) furs sold to the Hudson's Bay Company. Lynx eat snowshoe hares.

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orin stepanek wrote: ↑Mon Feb 01, 2021 5:25 pm

johnnydeep wrote: ↑Mon Feb 01, 2021 4:26 pm
My questions are in which direction were the two hares/rabbits going - to the trees or from them? And how close in time were their paths?

EDIT: actually I can now see that one path was from one of the trees and one path was toward the other one. And I guess it could even have been the same rabbit/hare!

Big feet probably a Jackrabbit--Hare went to trees on right & came back from trees on Left! Or it could be different ones!

https://en.wikipedia.org/wiki/Lotka%E2%80%93Volterra_equations wrote:
<<The Lotka–Volterra equations, also known as the predator–prey equations, are a pair of first-order nonlinear differential equations, frequently used to describe the dynamics of biological systems in which two species interact, one as a predator and the other as prey. The populations change through time according to the pair of equations:

---

where:

• x is the number of prey (for example, rabbits);
  y is the number of some predator (for example, foxes);
  t represents time;
  α, β, γ, δ are positive real parameters describing the interaction of the two species.

The Lotka–Volterra system of equations is an example of a Kolmogorov model, which is a more general framework that can model the dynamics of ecological systems with predator–prey interactions, competition, disease, and mutualism. The Lotka–Volterra models have been used to explain the dynamics of natural populations of predators and prey, such as the lynx and snowshoe hare data of the Hudson's Bay Company and the moose and wolf populations in Isle Royale National Park.>>