Solar eclipse from the Moon explanation (APOD 2 Mar 2007)

Comments and questions about the APOD on the main view screen.
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Chris Peterson
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Solar eclipse from the Moon explanation (APOD 2 Mar 2007)

Post by Chris Peterson » Fri Mar 02, 2007 6:01 am

Nice image, but it seems to me to be quite inaccurate. Scaling the image, the refracted and scattered sunlight is extending to a whopping 280 km altitude. I'd expect the majority of the scatter to be below 50 km or so; in this image that would be a ~2-3 pixel band of red around the edge rather than the 25 pixel band rendered.

An image like http://www.earthfromspace.si.edu/online ... stopPic=19 shows just how thin the atmosphere really is.
Chris

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Solar eclipse from the moon explanation. (APOD 2 Mar 2007)

Post by gardini » Fri Mar 02, 2007 9:42 am

Hello,

it seems to me that the last sentence in the explanation
(At the upper left, the Sun itself is just emerging from behind the Earth's limb)
states that the total phase of the eclipse has just ended,
while its should just begin.

An example of the path of the sun behind the earth is shown in the link
http://www.xs4all.nl/~carlkop/maaneclip ... s2007.html

-------------------------------------------------
Alessandro

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Earth Elipse

Post by Nilesh » Fri Mar 02, 2007 9:56 am

i doubt if earth surface should be so brigth during eclipse.
applying similar logic , features on moon should be visible during eclipse by moon, as earth reflect more light than moon
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Re: Solar eclipse from the Moon

Post by DaleA » Fri Mar 02, 2007 2:51 pm

Chris Peterson wrote:Nice image, but it seems to me to be quite inaccurate. Scaling the image, the refracted and scattered sunlight is extending to a whopping 280 km altitude. I'd expect the majority of the scatter to be below 50 km or so; in this image that would be a ~2-3 pixel band of red around the edge rather than the 25 pixel band rendered.

An image like http://www.earthfromspace.si.edu/online ... stopPic=19 shows just how thin the atmosphere really is.
Agreed. And is that jagged edge supposed to represent 100 km high mountains? Not up to the usual high APOD standard. :(

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Post by planetquinn » Fri Mar 02, 2007 3:50 pm

First, thanks to the artist who created the image and to APOD for posting it. I hope to see photos of an earth eclipse in my lifetime. This relates to a subject that intrigues me--how the earth-moon cycles have stimulated human thought. Some subtopics:

The 28-day lunar cycle allowed people sufficient experience in a 40-70 year lifetime to recognize and explain the mechanics. If the lunar cycle was longer than a lifetime I doubt we would have gotten very far in our understanding of celestial mechanics. It might have been beyond early humans to ever observe a sun-moon pattern. I think that observing and explaining the lunar cycles was key to the development of a rational view of the world.

What patterns could be observed by life developing on the far side of the moon? The cycles would be enigmatic without knowledge of the Earth. Would anybody be bold enough to suggest that there was a big invisible planet behind it all? Is there something similar operating for us—something we do not see?

Aren’t the poles of the moon prime real estate? Full-time sunlight, full-time observation of the Earth. Let’s stake our claim.

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Hello everybody and thanks for discussing my illustration

Post by hanag » Fri Mar 02, 2007 4:52 pm

I agree with Chris about the size of Earth's atmosphere - I even think that we'll probably will NOT see it by naked eye - only with binocles or even telescope, I also agree with Nelish - that the Lunar surface will be much durker and the Earth itself too, BUT becouse it's ONLY an ullustration I HAD to make some extrimes SO I could emfesize on the BEAUTY of readish atmosphere of OUR PLANET - where we all - human beings live - and how small and beutiful it is from outside. I also made it much bigger related to the Lunar surface - so again to show the beauty!
I'm so glad u enjoyed.
regards
Hana Gartstein, Israel

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Post by mkrupnick » Fri Mar 02, 2007 5:14 pm

The more glaring flaw in this composite is that the foreground illumination of the lunar surface is totally unconvincing. The shadows are all wrong, and the ambient spill would be much weaker and more diffused.

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Post by BMAONE23 » Fri Mar 02, 2007 5:53 pm

what it lacks in accuracy, I think it more than makes up for in beauty.

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Earth viewed from the Moon during lunar eclipse (2 Mar 2007)

Post by IknoIkno » Fri Mar 02, 2007 9:09 pm

Rather than saying that the Moon would be "surrounded with a red-tinted haze", I would recommend, just because of its dramatic (and borderline mind-blowing) effect, that the explanatory text tell the viewer that he/she would be viewing every sunrise and every sunset on Earth simultaneously.
JLP

The meek shall inherit the Earth, because the bold shall inherit the stars!

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Post by schmidtpcisys » Fri Mar 02, 2007 9:51 pm

Oh, Man. Great photo!

Please, please, please! Does anyone know where I can get this photo in a poster format? I. Must. Have. It!

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Post by NoelC » Sat Mar 03, 2007 3:37 am

It's an absolutely beautiful image!

People may nitpick, but it's art for goodness sake! And fine art at that.

I wish I'd thought of the concept. :)

-Noel

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the eclipse

Post by janlitwin » Sun Mar 04, 2007 10:22 pm

Haven't you noticed that viewed from the Moon the Earth would appear much larger in diameter than the Sun? Take into account the distances and the sizes of these celestial bodies.
Jan

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Oh no!

Post by appollo » Mon Mar 05, 2007 7:53 pm

I'm really disappointed about the image. What it shows is absolutely wrong. People, who watch it get a strange imagination of the solar system. What a pity that it was published on APOD! Shame on you.

The reasons:
1s: When a contact occurs during such an eclipse, there will neither be the effect called 'Bailey's Beads' nor a diamond ring! The corona will mostly be visible, where the sun disapperead - on Hannas image it seems that the sun has about the apparent size of earth (because the inner corona surrounds earth), but in fact it seems much smaller observed from the moon.

2nd: Furthermore the atmosphere doesn't glow in red in the illustartion - but in reality it does. The glow is so strong that we can see it during a lunar eclipse, reflected from the moon. The glow would be much brighter (yellow or white) if the sun is close to the rim.

3rd: One thing that shocked me most is that I can see surface structures of the earth in colour. What are they illuminated by? The reddish glim of the eclipsed moon could not illuminate the nightside of the earth so much. In comparison to the glowing atmosphere of the earth it would appear black and dark. Maybe one could see some citylights, but no clouds!

4th: But not enough: Some minutes ago I saw a more frustrating version on the image. It showed a wrong eclipse over the brightly illuminated lunar surface with an Apollo astronaut on it. What is the surface illuminated by? Why is it bright and white? Why do you waste your time creating such a nonsense...

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Better view

Post by appollo » Mon Mar 05, 2007 7:55 pm

Oh because of all my sudden frustration I forgot to tell you that I know an image which shows the view from the moon much better:
http://astrocorner.de/pics/archiv.php5? ... ternis.jpg

The image is not perfect, but much more perfect than Hannas issue.

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