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Old 24-08-2009, 08:07 PM
pete_pumpkin (Pete)
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Excuse my ignorance :) but..

I don't recall seeing the moon, the way it looks tonight. Like a big happy smile.. I only remember seeing the moons shadow either left or right off the lit bit. Looking at it now it's bright at the bottom and dark at the top. Is it the end of the world as we know it ?
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Old 24-08-2009, 08:21 PM
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mswhin63 (Malcolm)
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I have heard of Earthshine as a possible cause for this, maybe someone else can shed some light on this.
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Old 24-08-2009, 08:48 PM
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mental4astro (Alexander)
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Earthshine it is.

Light reflected from the earth is illuminating the moon's 'dark side' in much the same way that the moon illuminates the earth, say when it is full moon, casting shadows, & odliterating deep sky objects from view, .
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Old 24-08-2009, 09:37 PM
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erick (Eric)
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And the Earth is a huge shiny very reflective thing, compared to the Moon which is all a dull powdered rock and a lot smaller. So I think you'd be wearing your sunnies if you were standing in that earthshine-lit part of the Moon - much brighter than the full Moon shining on the Earth.

By the way, the smiley face Moon (OK, Crescent Moon), go directly out from the bottom of the smile and that is the direction to the Sun
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Old 24-08-2009, 10:09 PM
dpastern (Dave Pastern)
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I would have loved to have gotten the scope out tonight, but alas, I'm alway seem to be working late shift @ work when it's first crescent...by the time I get home, the moon is too low in the scow and obscured by buildings and trees

Dave
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Old 25-08-2009, 12:05 AM
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Lumen Miner (Mitchell)
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Quote:
Originally Posted by mental4astro View Post
Earthshine it is.

Light reflected from the earth is illuminating the moon's 'dark side' in much the same way that the moon illuminates the earth, say when it is full moon, casting shadows, & odliterating deep sky objects from view, .
Quote:
Originally Posted by erick View Post
And the Earth is a huge shiny very reflective thing, compared to the Moon which is all a dull powdered rock and a lot smaller. So I think you'd be wearing your sunnies if you were standing in that earthshine-lit part of the Moon - much brighter than the full Moon shining on the Earth.

By the way, the smiley face Moon (OK, Crescent Moon), go directly out from the bottom of the smile and that is the direction to the Sun
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Originally Posted by mswhin63 View Post
I have heard of Earthshine as a possible cause for this, maybe someone else can shed some light on this.
I don't think it is Earthshine he is talking about. I think he is asking why the moon is not is the "general" position of a "C" as the last moon phase.

Now it is positioned not as the picture to the left suggests, but as the cresent at the bottom...

I might just be way out of my depth here, but that's not earthshine, it's the current moon waxing crescent, just like a smiley face.

Am I wrong?

Maybe your right, I was wondering why the moon was on its side...
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Old 25-08-2009, 09:29 AM
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mental4astro (Alexander)
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, now I getz the question. Thanks Lumen.

It looks like it's on its side because of the position we are on the earth.

For example, right now it looks nearly cresent down. If you were on the equator, it would be totally down. If you were on the poles, it would appeare 'vertical' like the typical 'C' shape.

The moon's orbit is pretty much on the same plane as our equator, so its apparent phase's follow the same orientation. As the earth is round (I think it is, or is it flat), your viewing of the moon's angle of tilt would change as you move according to your latitude on the earth.

But the moon's orbit does 'move' like a wobbily disk, which is why, as another example, full moon one day could be overhead, & another lunar cycle it is much closer to the northern horizon. This too will influence its apparent orientation.

As Erick said, what remains constant is the position of the sun, perpendicular to the cresent.

Tricky bugger, eh.
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