APOD: Apollo 11 Landing Site Panorama (2018 Jul 21)

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APOD: Apollo 11 Landing Site Panorama (2018 Jul 21)

Post by APOD Robot » Sat Jul 21, 2018 4:11 am

Image Apollo 11 Landing Site Panorama

Explanation: Have you seen a panorama from another world lately? Assembled from high-resolution scans of the original film frames, this one sweeps across the magnificent desolation of the Apollo 11 landing site on the Moon's Sea of Tranquility. The images were taken by Neil Armstrong looking out his window of the Eagle Lunar Module shortly after the July 20, 1969 landing. The frame at the far left (AS11-37-5449) is the first picture taken by a person on another world. Toward the south, thruster nozzles can be seen in the foreground on the left, while at the right, the shadow of the Eagle is visible to the west. For scale, the large, shallow crater on the right has a diameter of about 12 meters. Frames taken from the Lunar Module windows about an hour and a half after landing, before walking on the lunar surface, were intended to initially document the landing site in case an early departure was necessary.

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Boomer12k
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Re: APOD: Apollo 11 Landing Site Panorama (2018 Jul 21)

Post by Boomer12k » Sat Jul 21, 2018 5:06 am

An outstanding achievement, and a nice shot...

I could not find a source for The Moon as being considered..."another world"...I am sure it is debatable... Is "Another World" considered only for Planets? Is there a definitive source for this, or is it just up to "writers choice"?

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Re: APOD: Apollo 11 Landing Site Panorama (2018 Jul 21)

Post by neufer » Sat Jul 21, 2018 12:42 pm

Boomer12k wrote:
Sat Jul 21, 2018 5:06 am

I could not find a source for The Moon as being considered..."another world"...I am sure it is debatable... Is "Another World" considered only for Planets? Is there a definitive source for this, or is it just up to "writers choice"?
  • While one might argue that a "world" requires living inhabitants
    (e.g., the Wide World of Sports, SeaWorld, etc.)
    it certainly has nothing in particular to do with the IAU official definition of a planet.

    (The Moon, at least temporarily, had two living inhabitants.)
https://www.etymonline.com/word/world wrote:
world (n.) Old English woruld, worold "human existence, the affairs of life." Originally "life on earth, this world (as opposed to the afterlife)," sense extended to "the known world," then to "the physical world in the broadest sense, the universe" (c. 1200).
Art Neuendorffer

ksp

Re: APOD: Apollo 11 Landing Site Panorama (2018 Jul 21)

Post by ksp » Sat Jul 21, 2018 7:44 pm

Apologies if this is a stupid question, but I've always been curious why there are no stars visible in the background in pictures such as this from the moon.

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Re: APOD: Apollo 11 Landing Site Panorama (2018 Jul 21)

Post by bystander » Sat Jul 21, 2018 8:02 pm

ksp wrote:
Sat Jul 21, 2018 7:44 pm
Apologies if this is a stupid question, but I've always been curious why there are no stars visible in the background in pictures such as this from the moon.
The same reason you can't see stars during the daytime on Earth, the foreground is too bright. The reason the sky is black is there is no atmosphere to scatter the light and turn the sky blue.
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk.
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Re: APOD: Apollo 11 Landing Site Panorama (2018 Jul 21)

Post by starsurfer » Sat Jul 21, 2018 10:36 pm

ksp wrote:
Sat Jul 21, 2018 7:44 pm
Apologies if this is a stupid question, but I've always been curious why there are no stars visible in the background in pictures such as this from the moon.
It's taken from the daylight side, people always claim this as proof that the moon landings were faked.

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Re: APOD: Apollo 11 Landing Site Panorama (2018 Jul 21)

Post by ta152h0 » Sun Jul 22, 2018 1:16 am

Exceptional people ....
Wolf Kotenberg

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Re: APOD: Apollo 11 Landing Site Panorama (2018 Jul 21)

Post by Boomer12k » Sun Jul 22, 2018 2:04 am

neufer wrote:
Sat Jul 21, 2018 12:42 pm
Boomer12k wrote:
Sat Jul 21, 2018 5:06 am

I could not find a source for The Moon as being considered..."another world"...I am sure it is debatable... Is "Another World" considered only for Planets? Is there a definitive source for this, or is it just up to "writers choice"?
  • While one might argue that a "world" requires living inhabitants
    (e.g., the Wide World of Sports, SeaWorld, etc.)
    it certainly has nothing in particular to do with the IAU official definition of a planet.

    (The Moon, at least temporarily, had two living inhabitants.)
https://www.etymonline.com/word/world wrote:
world (n.) Old English woruld, worold "human existence, the affairs of life." Originally "life on earth, this world (as opposed to the afterlife)," sense extended to "the known world," then to "the physical world in the broadest sense, the universe" (c. 1200).
Thanks, Neufer...I know we use the term...it just struck me as ODD at the moment...and it made me wonder...I was thinking, "astronomical body"...but that is cumbersome...
Thanks for your answer.

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LMMdT

Re: APOD: Apollo 11 Landing Site Panorama (2018 Jul 21)

Post by LMMdT » Mon Jul 23, 2018 7:38 am

bystander wrote:
Sat Jul 21, 2018 8:02 pm
ksp wrote:
Sat Jul 21, 2018 7:44 pm
Apologies if this is a stupid question, but I've always been curious why there are no stars visible in the background in pictures such as this from the moon.
The same reason you can't see stars during the daytime on Earth, the foreground is too bright. The reason the sky is black is there is no atmosphere to scatter the light and turn the sky blue.
I thought that the scattered light was precisely what prevented us from seeing the stars.

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Re: APOD: Apollo 11 Landing Site Panorama (2018 Jul 21)

Post by Chris Peterson » Mon Jul 23, 2018 1:31 pm

LMMdT wrote:
Mon Jul 23, 2018 7:38 am
bystander wrote:
Sat Jul 21, 2018 8:02 pm
ksp wrote:
Sat Jul 21, 2018 7:44 pm
Apologies if this is a stupid question, but I've always been curious why there are no stars visible in the background in pictures such as this from the moon.
The same reason you can't see stars during the daytime on Earth, the foreground is too bright. The reason the sky is black is there is no atmosphere to scatter the light and turn the sky blue.
I thought that the scattered light was precisely what prevented us from seeing the stars.
There is "seeing" and there is "imaging". They operate in somewhat different domains with respect to dynamic range. Scattering is certainly a factor. If you were on the Moon during the day, and looked at the sky from the bottom of a well, you'd see stars. Not so on Earth. But with images, it really just comes down to dynamic range and object brightness. There's not much difference in brightness between a daytime scene on the Moon and one on the Earth. In either case, with a film camera, you might have an exposure time of a hundredth of a second or less. Set up your camera for a well exposed shot during the day, and now wait for nighttime. Take a shot using the same settings. How many stars do you capture? Probably none, and certainly not a sky full of them. That's what's happening on lunar shots. You have daytime exposure settings. The lack of atmospheric scatter means the sky looks black, but the stars are so much dimmer than the foreground that they don't rise above the noise. You could see stars in a daytime lunar image, simply by making a several second long shot. Of course, the landscape would be massively overexposed, and there'd still be glare in the optics interfering with the image.
Chris

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