The dumb questions thread

[Angry Floof]

Why do craters and other depression landforms so often appear to be convex in aerial photos?

 

[steve_bank]

My guess is the distribution of energy. The crater is deeper in the middle and diminishes by maybe 1/r^2. I think both heat and acoustic energy may diminish 1/r^2. Maybe there is a wiki page on explosive's blast energy.

There are also mushroom clouds.

Bomb craters.

 

[fromderinside]

My guess is the distribution of energy. The crater is deeper in the middle and diminishes by maybe 1/r^2. I think both heat and acoustic energy may diminish 1/r^2. Maybe there is a wiki page on explosive's blast energy.

There are also mushroom clouds.

Bomb craters.

Well you tried steve_bank. Angry Floof didn't ask why craters had the shape they have. She asked whether the process of photography or some optical illusion inherent in humans perception produce the illusion that the crater is a dome.

From  Crater illusion

The Crater Illusion also known as the Crater/Dome Illusion or Dome Illusion is an optical illusion which causes impact craters in some images to appear as domes or mountains.^[1] It is believed to be caused by our being accustomed to seeing light from overhead.^[2] When some images are taken from orbit, the light from the sun is nearly horizontal. This is the only time shadows are seen. Our brains are tricked into thinking that the interior of the crater is above the surrounding terrain instead of below it

 

[bigfield]

Why do craters and other depression landforms so often appear to be convex in aerial photos?

Might be related to  Hollow-Face_illusion

 

[steve_bank]

Well then they appear circular because they are circular...

A high speed abject stinking the moon almost instantaneosly converts kinetic energy to heat and deformation of the surface and ejecting material.

It is spherical because the energy propagates as if originating form a small point radiating in all directions, IOW 1/r^2.

There is a picture of a micro meteorite strike on a space shuttle window. A somewhat spherical hole.

https://www.scienceabc.com/nature/u...-the-moon-round-and-not-some-other-shape.html

 

[James Brown]

Steve, her question has nothing to do with the shape of the crater. It has to do with the appearance of the crater.

 

[Kharakov]

Steve has very poor eyesight. Perhaps he doesn't understand the illusion... or what hylidae means.

 

[steve_bank]

Thank you for ending my Sunday with a great bug belly ligh.

I will decline an ensuing debate on the appearance of a crater and what it really looks like.

 

[Wiploc]

https://www.thehits.co.nz/random-st...pletely-divided-which-way-up-do-you-see-them/

 

[DBT]

Nice illusion.

 

[Wiploc]

Nice illusion.

I agree. They look like plates, but they're really meteor craters.

 

[fromderinside]

Wiploc!

 

[Angry Floof]

Nice illusion.

I agree. They look like plates, but they're really meteor craters.

My guess is the distribution of energy. The crater is deeper in the middle and diminishes by maybe 1/r^2. I think both heat and acoustic energy may diminish 1/r^2. Maybe there is a wiki page on explosive's blast energy.

There are also mushroom clouds.

Bomb craters.

Well you tried steve_bank. Angry Floof didn't ask why craters had the shape they have. She asked whether the process of photography or some optical illusion inherent in humans perception produce the illusion that the crater is a dome.

From  Crater illusion

The Crater Illusion also known as the Crater/Dome Illusion or Dome Illusion is an optical illusion which causes impact craters in some images to appear as domes or mountains.^[1] It is believed to be caused by our being accustomed to seeing light from overhead.^[2] When some images are taken from orbit, the light from the sun is nearly horizontal. This is the only time shadows are seen. Our brains are tricked into thinking that the interior of the crater is above the surrounding terrain instead of below it

Thanks! That makes the most sense. I've seen the plate image (and the dancer image, etc.) and it's easy to "flip" them in my mind when I want to, but aerial images of craters won't cooperate, so I knew there must be some explanation specific to craters' size and/or aerial imagery.

 

[Wiploc]

If we assume the light is coming from the right, then we are looking down into the plates. But if the light is from the left, then the plates are upside down, protruding up towards us.

 

[Angry Floof]

If we assume the light is coming from the right, then we are looking down into the plates. But if the light is from the left, then the plates are upside down, protruding up towards us.

Yeah, that's what I see when I look at the plates. I can imagine the direction of the light and see them either way. Images of craters don't cooperate, though.

 

[Wiploc]

Post a link, or an image of an upside down crater, if you would.

 

[James Brown]

Here's a picture of a uplifted mountain on Mars, mostly flat on top like an American Southwest mesa:

Show

Show

Actually, no. It's a picture of Victoria Crater, but flipped.

Show

 

[DBT]

Here's another one.

 

[Jimmy Higgins]

View attachment 21367
https://www.thehits.co.nz/random-st...pletely-divided-which-way-up-do-you-see-them/

Darn intelligently designed brains! I can switch back to the plates being upside down (just blink), but it is much harder to get them right side up without looking around.

 

[Wiploc]

If we assume the light is coming from the right, then we are looking down into the plates. But if the light is from the left, then the plates are upside down, protruding up towards us.

Yeah, that's what I see when I look at the plates. I can imagine the direction of the light and see them either way. Images of craters don't cooperate, though.

I can't make it work with the craters.

For that matter, I can no longer make it work with the plates.