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Originally Posted by Renton:

Fluffy - question!!!

i did psychology and read aobut visual illusions - one called Moon Illusion where the moon looks massive in the sky

I never quite understood or believed it

So why does the moon sometimes look absolutely massive?

Going to look heeeeeyooooge tomorrow, there's a perigee .. the closest point of the moon to the earth , and it pretty much coincides with the full moon  .  Please let there not be clouds!

FM
Originally Posted by Extremely Fluffy Fluffy Thing:
Originally Posted by Slinkiwitch x:

and here's the moon illusion explained ..http://facstaff.uww.edu/mccreadd/

And now that we've all studied that in depth, ( ) are we any the wiser?

 

I started reading it last night, but fell asleep.

I've read it and I'm none the wiser. I'll just accept that the moon sometimes looks huge.

Lots of twinkly stars last night, the sky looked very pretty.

Yogi19

Without having deciphered that ^^^^ yet, I'll give you what I have always understood about why that illusion happens.

 

Imagine, if you will, that THE ATMOSPHERE is a band of a fixed thickness.

When we look up we are looking directly through through this 'band'.

The closer to the horizon we look the more of an angle through this 'band' we are looking, thus a greater 'thickness' of atmosphere.

Because of the distortion to the light this causes we perceive the size of the moon as larger than it really is.

 

I.E. The greater the amount of atmosphere we have to look through the greater the distortion in size.

 

Lots of atmosphere at the horizon = huge moon.

Medium amount of atmosphere 'half way up' the sky = medium sized moon.

Least amount of atmosphere 'up high' = small moon.

 

Because of the PERIGEE state tonight (it's closer, therefor looks bigger to start with) the illusion is going to makethe moon at the horizon even bigger, thus the term 'Supermoon'.

Extremely Fluffy Fluffy Thing
Originally Posted by Extremely Fluffy Fluffy Thing:

Without having deciphered that ^^^^ yet, I'll give you what I have always understood about why that illusion happens.

 

Imagine, if you will, that THE ATMOSPHERE is a band of a fixed thickness.

When we look up we are looking directly through through this 'band'.

The closer to the horizon we look the more of an angle through this 'band' we are looking, thus a greater 'thickness' of atmosphere.

Because of the distortion to the light this causes we perceive the size of the moon as larger than it really is.

 

I.E. The greater the amount of atmosphere we have to look through the greater the distortion in size.

 

Lots of atmosphere at the horizon = huge moon.

Medium amount of atmosphere 'half way up' the sky = medium sized moon.

Least amount of atmosphere 'up high' = small moon.

 

Because of the PERIGEE state tonight (it's closer, therefor looks bigger to start with) the illusion is going to makethe moon at the horizon even bigger, thus the term 'Supermoon'.

That basically sums up the visual angle illusion theory they waffle about on that link! 

When the moon comes up, if you do the " I'm crushing your head" thing ( close one eye, put one finger at the top you see of the moon, one at the bottom ) when it looks huge, the space between your fingers will be exactly the same as if you do it when the moon is high ( and much smaller looking)

FM
Originally Posted by Extremely Fluffy Fluffy Thing:
Originally Posted by Yogi19:

I can see Venus when I go into the front garden and Lyra (I think) when I go into the back garden, but no sign of the moon.

I'll hazard a guess and say it's probably Arcturus or Vega that you're seeing, not Lyra. Vega is about quareter of the way up the sky and Arcturus is half way up.

I'll take your word for it. I was just guessing going by the star gazer app on son's ipad.

Yogi19
Originally Posted by Extremely Fluffy Fluffy Thing:

There's a sort of brightness behind the trees....I think the moon must be out....

 

....and when I look out of the upstairs window I can see it....just! It's still behind the trees, but near the tops, so I can see it a bit, but no real idea of apparent size.

Yes, there's a brightness behind some neighbouring houses - but they are a bit higher up than me, so I can't see the moon.

Yogi19
Originally Posted by Yogi19:
Originally Posted by Extremely Fluffy Fluffy Thing:
Originally Posted by Yogi19:

I can see Venus when I go into the front garden and Lyra (I think) when I go into the back garden, but no sign of the moon.

I'll hazard a guess and say it's probably Arcturus or Vega that you're seeing, not Lyra. Vega is about quareter of the way up the sky and Arcturus is half way up.

I'll take your word for it. I was just guessing going by the star gazer app on son's ipad.

Lyra is actually the name of the constellation, the principal star of which is Vega.

Given the hazyness of my sky, I doubt that you would be able to see all the stars that make up Lyra.

Extremely Fluffy Fluffy Thing
Originally Posted by Extremely Fluffy Fluffy Thing:
Originally Posted by Yogi19:
Originally Posted by Extremely Fluffy Fluffy Thing:
Originally Posted by Yogi19:

I can see Venus when I go into the front garden and Lyra (I think) when I go into the back garden, but no sign of the moon.

I'll hazard a guess and say it's probably Arcturus or Vega that you're seeing, not Lyra. Vega is about quareter of the way up the sky and Arcturus is half way up.

I'll take your word for it. I was just guessing going by the star gazer app on son's ipad.

Lyra is actually the name of the constellation, the principal star of which is Vega.

Given the hazyness of my sky, I doubt that you would be able to see all the stars that make up Lyra.

Ah, in that case, I could see Vega.

Yogi19
Originally Posted by Slinkiwitch x:
Originally Posted by Yogi19:

Thanks for the heads up, Fluffy, I'll look out for it.

Why is Veggie's avi now saying "Guest"? Has she left us, as well as Gypsie?

Just noticed that Yogi.  veggie's been a member  here as long as I can remember , really sorry she's gone .

Me too.

Along with Scotty and Savannah, Veggie was one of the first people to "talk" to me on CH4 forums.

Yogi19

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