APOD: Partial Solar Eclipse over Argentina (2022 May 02)

Post a reply


This question is a means of preventing automated form submissions by spambots.
Smilies
:D :) :ssmile: :( :o :shock: :? 8-) :lol2: :x :P :oops: :cry: :evil: :roll: :wink: :!: :?: :idea: :arrow: :| :mrgreen:
View more smilies
BBCode is ON
[img] is ON
[url] is ON
Smilies are ON
Topic review
   

Expand view Topic review: APOD: Partial Solar Eclipse over Argentina (2022 May 02)

Re: APOD: Partial Solar Eclipse over Argentina (2022 May 02)

by longtry » Wed Sep 21, 2022 3:10 am

While I appreciate the Timestorm video link buried deep within the article (and the writer's apparent mindset of rewarding those who are diligent with a beautiful clip), I think it should be more prominently displayed. Such a good video can make someone's day.

Re: APOD: Partial Solar Eclipse over Argentina (2022 May 02)

by Chris Peterson » Mon May 02, 2022 6:17 pm

De58te wrote: ↑Mon May 02, 2022 6:02 pm
J Weber wrote: ↑Mon May 02, 2022 7:18 am Why does it appear that a section of the Sun has been cut away so that we can see the clouds on the other side of the Sun? We cannot see through the Sun! Shouldn't the top left section of the Sun be dark (not full of clouds) from the Earth blocking our view so we should see nothing but a darkened area?
The left section is the partly eclipsing Moon. Now when the Moon is new, we on Earth can't see the Moon at all since the side facing us is black as night. So why does the Moon look orange? Now during total Lunar eclipse we don't see the complete dark shadow of the Earth, but we see the red Earthshine reflecting back from the Moon. This here is certainly not Earthshine, and here's why. I took a look at the camera stats on the photographer's site under the 'featured image' link. They used a single lens reflex lens with an ISO of 100 (To most purposes that is daylight film. The standard of taking daylight pictures without using a flash. The sensitivity to light is not very great.), an f-stop of 29 ( now that is extremely small aperture. It's a pinhole camera. My SLR camera only went to f-stop 16, which was more than enough for my purposes. A small aperture will take a photo of somebody standing say 5 feet away and still make the background hundreds of feet away crisp and in focus. If you want a blurred background, increase the aperture to under 4.) And a shutter speed of 1/8000 a second. ( Now that is super fast! An ordinary everyday camera would have a speed of 1/60 to 1/120 a second.) Now I can assure you that if you took a picture of the Lunar eclipse at speed 1/8000, you'd see nothing but darkness. The speed is way too fast for light to affect the photo receptors.) This APOD is virtually like looking through welder's glasses. I'm surprised the clouds showed up at all. The light on the Moon must have only happened in the Earth's atmosphere. The light surrounding the Sun is so bright that enough reflected off the clouds bounced back to the Moon and then back to the camera. (Just my opinion. I am not a scientific expert.)
The forward scatter from water droplets is significant. A thin cloud between the Sun and our eyes is blindingly bright. We just don't usually see it because of the dazzle of the Sun itself. But by limiting the exposure to the point where the Sun is merely bright and the sky is black, it's not at all surprising we would see clouds nearly in line with the Sun.

Re: APOD: Partial Solar Eclipse over Argentina (2022 May 02)

by De58te » Mon May 02, 2022 6:02 pm

J Weber wrote: ↑Mon May 02, 2022 7:18 am Why does it appear that a section of the Sun has been cut away so that we can see the clouds on the other side of the Sun? We cannot see through the Sun! Shouldn't the top left section of the Sun be dark (not full of clouds) from the Earth blocking our view so we should see nothing but a darkened area?
The left section is the partly eclipsing Moon. Now when the Moon is new, we on Earth can't see the Moon at all since the side facing us is black as night. So why does the Moon look orange? Now during total Lunar eclipse we don't see the complete dark shadow of the Earth, but we see the red Earthshine reflecting back from the Moon. This here is certainly not Earthshine, and here's why. I took a look at the camera stats on the photographer's site under the 'featured image' link. They used a single lens reflex lens with an ISO of 100 (To most purposes that is daylight film. The standard of taking daylight pictures without using a flash. The sensitivity to light is not very great.), an f-stop of 29 ( now that is extremely small aperture. It's a pinhole camera. My SLR camera only went to f-stop 16, which was more than enough for my purposes. A small aperture will take a photo of somebody standing say 5 feet away and still make the background hundreds of feet away crisp and in focus. If you want a blurred background, increase the aperture to under 4.) And a shutter speed of 1/8000 a second. ( Now that is super fast! An ordinary everyday camera would have a speed of 1/60 to 1/120 a second.) Now I can assure you that if you took a picture of the Lunar eclipse at speed 1/8000, you'd see nothing but darkness. The speed is way too fast for light to affect the photo receptors.) This APOD is virtually like looking through welder's glasses. I'm surprised the clouds showed up at all. The light on the Moon must have only happened in the Earth's atmosphere. The light surrounding the Sun is so bright that enough reflected off the clouds bounced back to the Moon and then back to the camera. (Just my opinion. I am not a scientific expert.)

Re: APOD: Partial Solar Eclipse over Argentina (2022 May 02)

by Chris Peterson » Mon May 02, 2022 1:25 pm

J Weber wrote: ↑Mon May 02, 2022 7:18 am Why does it appear that a section of the Sun has been cut away so that we can see the clouds on the other side of the Sun? We cannot see through the Sun! Shouldn't the top left section of the Sun be dark (not full of clouds) from the Earth blocking our view so we should see nothing but a darkened area?
If you were viewing this visually, nothing would be dark. The Sun would be blindingly bright, there would be thin bright clouds, and a blue sky. Through a strong neutral density filter, the sky looks black, the Sun is only slightly overexposed, and the clouds are still bright enough to not be entirely blocked.

Re: APOD: Partial Solar Eclipse over Argentina (2022 May 02)

by orin stepanek » Mon May 02, 2022 12:44 pm

PartialEclipse_Andrada_960.jpg
Sun so bright it shines right through the clouds! I've seen this
phenomena while looking out of window on a cloudy day at rehab &
:shock: the sun breaks through the overcast!
2220_Eclipse_Panel-1280x900.jpg
A bite out of the cookie!
.gif
Click on to view! neat! 8-)

Re: APOD: Partial Solar Eclipse over Argentina (2022 May 02)

by Ann » Mon May 02, 2022 9:06 am

J Weber wrote: ↑Mon May 02, 2022 7:18 am Why does it appear that a section of the Sun has been cut away so that we can see the clouds on the other side of the Sun? We cannot see through the Sun! Shouldn't the top left section of the Sun be dark (not full of clouds) from the Earth blocking our view so we should see nothing but a darkened area?
I guess that what we are seeing is the partly eclipsed Sun seen against a sky covered in thin clouds. The eclipsed Sun is shining through that sort of cloud cover in today's APOD, but because the Sun is overexposed, we don't see the clouds in front of the "crescent" of the Sun. But the clouds are still there, and they are obvious in front of the Moon - which is doing the eclipsing - and in the background sky.

Sun through clouds Dreamstime.png
The Sun shining through thin clouds.
Overexposed Sun through clouds Dreamstime.png
An overexposed Sun shining through thin clouds.
No clouds can be seen across the face of the Sun.
Ann

Re: APOD: Partial Solar Eclipse over Argentina (2022 May 02)

by J Weber » Mon May 02, 2022 7:18 am

Why does it appear that a section of the Sun has been cut away so that we can see the clouds on the other side of the Sun? We cannot see through the Sun! Shouldn't the top left section of the Sun be dark (not full of clouds) from the Earth blocking our view so we should see nothing but a darkened area?

Re: APOD: Partial Solar Eclipse over Argentina (2022 May 02)

by Steve Dutch » Mon May 02, 2022 4:33 am

Many APOD links are useless. Instead of specifics about the pcoming eclipses mentioned, the links go to generic articles on eclipses and even the definition of North America. You might as well not bother.

APOD: Partial Solar Eclipse over Argentina (2022 May 02)

by APOD Robot » Mon May 02, 2022 4:05 am

Image Partial Solar Eclipse over Argentina

Explanation: What's happened to the Sun? Two days ago, parts of South America were treated to a partial solar eclipse -- where the Moon blocked out part of the Sun. The featured image shows an image of the partially eclipsed Sun through clouds as it was setting over Patagonia, Argentina. In the tilted image, Earth is toward the right. During the eclipse, the Moon moved partly between Earth and the Sun. Although a visually impressive sight, the slight dimming of surroundings during this partial eclipse was less noticeable than dimming created by a thick cloud. In about two weeks, all of South America and part of North America will experience a total lunar eclipse -- where the Earth moves completely between the Moon and the Sun. In about two years, a total solar eclipse will cross North America.

<< Previous APOD This Day in APOD Next APOD >>

Top