"All that is now
All that is gone
All that's to come
and everything under the sun is in tune
but the sun is eclipsed by the moon." -Pink Floyd
No matter how well-prepared you were for your first total solar eclipse, no amount of reading or photograph-searching could do the experience justice. There were so many things to feel, see, and be overwhelmed by that you literally needed to be there to relate to. Yet it was remarkable how many things there were that surprised scientists and skywatchers alike.
The temperatures really did plummet, and they dropped by more than even the weather models predicted. There was a star and a planet visible, but not the planets we thought would arrive. The sky turned red along the horizon, which was a mystery for centuries, even after we learned why the sky is blue. And the light, the way it looked across the landscape, was a unique treat that you'll never experience during any other time than an eclipse itself.
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... there is no dark side of the Moon really, as a matter of fact it's all dark ;)
Reading your article it's clear that you had a blast and that you're still under emotional experience of it. :) I'm glad and happy that you had good weather and that it was great.
But can't really understand why points 1, 2, 6 and 9 are surprising, especially for scientists.
One thing that surprised me, was the impression of how deeply black the Moon appeared. It was like a hole of nothingness in the sky. I think that great contrast between the corona and the Moon is what makes the view so different from photographs.
But the question is - why the Moon seems so black during totality? The rest of the sky, beyond the Sun's corona, is bright because of the light refracted in the atmosphere. Since the Moon is far beyond the atmosphere, shouldn't it be washed away by the refracted light and appear the same color as the rest of the sky?
It could be explained as an optical illusion - how our eyes and brain react to the huge contrast. But the photographs, like the one above, prove that it actually is darker than the sky.
you said "By time totality was over, the temperature had cooled down to 65 degrees F, a drop of 17 degrees! Even with no clouds in the sky, the effect was spectacular, and aligned with some of the more significant historical drops ever recorded."
I wonder if you were at a place with really low dew point. In the East, dew point was low 70's.
@Pawel wrote:
...or it could be explained by Ethan in an article posted about 4 days ago. Just sayin'
http://scienceblogs.com/startswithabang/2017/08/16/why-you-cant-see-the…
just to add to denier's comment... a cemera/photograph works in much the same way as the eye does. In order to get a photo of the corona and not wash out the rest of the image, you have to set the exposure and shutter (or ccd sensitivity these days), thus the moon will be black.
I took my wife who's not a scientist- she likes science when she sees it but really just hasn't had the time for it (a medic). For example, it wasn't that long ago she asked "So, the sun is a star, right?". When we went to the eclipse she asked me how it happened and i explained how the sun moved between the earth and the moon, which she bought for a while. This is what we (I) are dealing with ;-) So why do i say this?
When the totality happened, after a look around and a few seconds of it she cried. I have only seen this woman cry once in our 30+ years together at a natural event, and that was when we were new to America on honeymoon part three, and went to Yosemite. The first thing we did of course was drive up the mountain to the overlook. Got out of the car, walked to the view and in less than a minute she cried.
Thats the measure of totality to me - and my first time too. You gotta see to appreciate the wonder that it is. Its not surreal, unreal or other-wordly. Its wondrously very very real.
We got lucky in Clayton, Georgia. After a clear day big clouds moved in that left many racing off in their cars and others walking away in unjustified disgust. But just at the last minute a gap opened up. For just a bit longer than needed. Lucky or what?
BTW I was starring hard, but I was pretty sure I saw Mars, close to and to the left of the sun, at about 11 o-clock. Am I deluded?
Oh, and we went to a bar after to wait out the traffic. Channel 2 was covering the eclipse. The reporter was sat in front of a time lapse eclipse backdrop. And her name was Wendy Corona. I kid you not. I have a photo. And i looked her up - real newswoman.
Oh BTW, the surprise I wasn't ready for?
Stupid, but what can you do.
I was aware that it was getting cooler and darker, but since your eye is a difference engine, you kinda can't be sure as it adjusts.
Yea, its getting darker right? Are you sure?
And then the street lights came on, in the middle of the day!!.
Welcome to the club, Ethan. You seem to show the signs. More, more! Next eclipse, please! At least the next one will see you better prepared now you have first hand experience of the event.
:)
I did think this article was interesting. I saw mention of this in one of my physics texts years ago, but his has far better pictures.
Why settle for looking at one lunar eclipse when you can literally look at hundreds at the same time?
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https://wattsupwiththat.com/2017/08/22/eclipsified-leaf-gap-shadows-nat…
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@Jonathan, @Denier, neither the article nor the contrast explains my main point, why it is rather than the sky. Or am I missing something?
@Jonathan, @Denier, neither the article nor the contrast explains my main point, why it is darker than the sky. Or am I missing something?
@Pawel Zuzelski #11,
I think what you are referring to is
the sky (or the gases in the atmosphere) is still refracting a lot of light even during an eclipse much like it does in the evening when the sun is going down behind a mountain or hill. You might recall that the hill the sun goes behind will look quite dark or black in comparison even if the sky above it is still quite colorful with the sunset.
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https://unsplash.com/search/photos/sunset?photo=ZzUZW7WxmPs
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A former classmate had posted pictures of his tree leaf eclipse images from '79 next to the tree leaf images at his current home from Monday. We have almost entirely Ponderosa pine trees in our yard, and needles don't make very good camera obscuras. We had eclipse glasses, a pinhole projector made from manila stock, a shoebox imager with holes on both a long and short side, and welders glass. We were at 92%, and the artificial dusk produced at maximum was pretty eerie, but the reduction in the heat emanating was a bit more so even. Even with the expectation of it happening.
I recall making shoebox imagers with Dad for the '79 eclipse. Interestingly we had to make the holes in our imagers pencil-sized before we got an image to work with.
@Pawel #11: At it simplest, anything imaged directly in front of a much brighter background will always look black and featureless. This happens regardless of whether the image is on film, and electronic photo sensor, or your eye. They all work on the same principle. It's why driving in a car directly towards a bright horizon after sundown or before sunrise can be dangerous - you can't see squat on the road.
Things that capture images work best when the incoming light is evenly distributed, because all the light is going through a single lens, which can have only be set to one opening size. Big differences in light distribution within the image causes a problem. A bigger opening is needed to capture enough light from the dark parts to "see" the details, while a small opening is needed to prevent too much light from being captured from the bright parts of the image. Not enough light and all you see is black (absence of light), while too much light makes the image just a patch of whiteness (excess of light). Somehow, the imaging device has to find a compromise.
@ pawel
it's not darker then the sky. it's the same black... you might perceive it as darker because corona is going outwards (gradient).
https://en.wikipedia.org/wiki/Cornsweet_illusion
I have to say that the experience has made me think a lot about what it must have been like back in the day, when you had no idea what was going on. Going about your day for decades with surety that all is well and fixed (I won't get religious) and then all of a sudden, in the middle of the day, it gets night for a couple of minutes ad then back again.
I am sure i would've pooped my pants.
Thanks for responses, but I am still not convinced.
@Sinisa Lazarek the picture above shows that's not Cornsweet illusion. You can inspect pixels and see the Moon is actually darker (unless heavy image processing was involved, but it doesn't seem so). Or are you saying that overexposed corona affects nearby pixels causing underexposure of the Moon? I don't think sensors work that way (though the human eye does).
@CFT you make an excellent point about the hill. However the hill blocking the sun appears dark only if it is nearby and there is not enough atmosphere in front of it. If the hill was in the distance comparable or larger than the thickness of the atmosphere, then it would be the same color as the rest of the sky.
@ pawel
I am not starting to think that you are just trolling. If you don't trust your eyes, open the above picture (image credit: Bratt Boller) in photoshop or some other software and sample the pixels. Moon: R:2 G:2 B:2, sky: R:1 G:1 B:1
Still saying moon is darker?
ups.. should be "now" instead of "not"
@Pawel Zuzelski,
No, the distance doesn't really make too much difference, as long as it is in line of sight and the sun is close to, or behind it, it will appear black. You are viewing a sillouette pretty much because the light source is behind whatever you are looking at and your eyes are interpreting the difference in contrast between the light source and the non light emitting object as black. If the sun were higher in the sky, or you were looking back behind you at something illuminated by setting sun, you would still see some color and detail.
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Go outside tomorrow, look up towards the sun with your hand blocking out the sun entirely so you don't damage your eyes and see what color your hand appears to be, your hand should be in silhouette or contrast against the brightness of the sun.
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https://www.masterfile.com/image/en/700-00061661
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@CFT nice halo on that picture! The hand blocking the sun appears darker then the sky, because there is not enough air between the hand and the camera to scatter the light. Again, the high contrast between the Moon and the corona explains why the Moon appears so dark to the eye. But the camera sensor should preserve relative brightness between the Moon and the background sky, regardless of the corona. The top picture shows that the moon is darker. So there must be something more going on than just contrast.
@Sinisa no, I am not trolling. You are probably referring to the second picture in the article, in which the background sky indeed appears dark. I am referring to the first image, the one with the eclipsed sun in top-left image and a tree and a photographer in bottom right corner.
@ pawel
in the first image the moon is just as dark as the tree and the photographer. Don't understand your dilemma. You might as well ask, why is the tree so dark. But this was explained to you in the beginning, if you want to take a properly exposed photo of the corona, due to the extreme brightness of the sun, you have to compensate and use very short exposure and shutter opening, thus everything else will be very underexposed. It needn't be the sun... ever saw a photo of someone lit from behind by a strong light? i.e.
https://ak8.picdn.net/shutterstock/videos/21486499/thumb/1.jpg
pretty standard photography. It's just the way things work. Unless you're doing HDR, but that's using composites of different exposures.