APOD: Sunrise at Copernicus Crater (2019 May 30)

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APOD: Sunrise at Copernicus Crater (2019 May 30)

Post by APOD Robot » Thu May 30, 2019 4:08 am

Image Sunrise at Copernicus Crater

Explanation: A prominent impact site anchored in the lunar Oceanus Procellarum, Copernicus crater is at the center of this telescopic portrait in light and shadow. Caught in stacked and sharpened video frames recorded on April 14 at 3:30am UTC, the lunar terminator, or boundary between night and day, cuts across the middle of the 93 kilometer diameter crater. Sunlight is just beginning to strike its tall western walls but doesn't yet shine on lower terrain nearby, briefly extending the crater's outline into the lunar nightside. At that moment standing at Copernicus crater you could watch the sunrise, an event that happens at Copernicus every 29.5 days. Of course that corresponds to a lunar month or a lunation, the time between consecutive Full Moons, as seen from planet Earth.

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Re: APOD: Sunrise at Copernicus Crater (2019 May 30)

Post by De58te » Thu May 30, 2019 7:18 am

Cool. So if you (an astronaut) were standing just on the rim of that eastern lookout, and looking to the west, you would see those bright white stretch of cliffs just hovering in the black darkness? Is there an artist listening who can draw an artist's interpretation? Could you see the stars behind it or would it be too bright to wash out the stars? Planet Earth would be somewhat hanging overhead, and if this was sunrise, then the Earth would be looking like a crescent Earth? That indeed would be an interesting artist's impression.

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Re: APOD: Sunrise at Copernicus Crater (2019 May 30)

Post by orin stepanek » Thu May 30, 2019 11:25 am

Nice video as seen from planet Earth! :D https://apod.nasa.gov/apod/ap180912.html
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Re: APOD: Sunrise at Copernicus Crater (2019 May 30)

Post by Chris Peterson » Thu May 30, 2019 12:37 pm

De58te wrote:
Thu May 30, 2019 7:18 am
Cool. So if you (an astronaut) were standing just on the rim of that eastern lookout, and looking to the west, you would see those bright white stretch of cliffs just hovering in the black darkness? Is there an artist listening who can draw an artist's interpretation? Could you see the stars behind it or would it be too bright to wash out the stars? Planet Earth would be somewhat hanging overhead, and if this was sunrise, then the Earth would be looking like a crescent Earth? That indeed would be an interesting artist's impression.
An observer on the Moon would always see stars in the sky, day or night.
Chris

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neufer
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Re: APOD: Sunrise at Copernicus Crater (2019 May 30)

Post by neufer » Thu May 30, 2019 1:36 pm

Chris Peterson wrote:
Thu May 30, 2019 12:37 pm
De58te wrote:
Thu May 30, 2019 7:18 am

Cool. So if you (an astronaut) were standing just on the rim of that eastern lookout, and looking to the west, you would see those bright white stretch of cliffs just hovering in the black darkness? Is there an artist listening who can draw an artist's interpretation? Could you see the stars behind it or would it be too bright to wash out the stars? Planet Earth would be somewhat hanging overhead, and if this was sunrise, then the Earth would be looking like a crescent Earth? That indeed would be an interesting artist's impression.
An observer on the Moon would always see stars in the sky, day or night.
https://www.quora.com/Why-do-astronauts-disagree-on-seeing-stars-in-space-Why-did-Aldrin-say-he-didnt-see-stars-but-the-astronauts-on-the-ISS-say-they-do wrote:
Click to play embedded YouTube video.
00:47:25: Patrick Moore: “…When you looked up at the sky, could you actually see the stars in the Solar Corona in spite of the glare

00:48:23: Armstrong answers about stars. “We were never able to see stars from the lunar surface or on the daylight side of the Moon without looking through the optics. I don’t recall during the time we were photographing the Solar Corolla (sic) what stars we could see.

00:48:40: Collins: “I can’t recall seeing any”
Art Neuendorffer

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Chris Peterson
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Re: APOD: Sunrise at Copernicus Crater (2019 May 30)

Post by Chris Peterson » Thu May 30, 2019 1:51 pm

neufer wrote:
Thu May 30, 2019 1:36 pm
Chris Peterson wrote:
Thu May 30, 2019 12:37 pm
De58te wrote:
Thu May 30, 2019 7:18 am

Cool. So if you (an astronaut) were standing just on the rim of that eastern lookout, and looking to the west, you would see those bright white stretch of cliffs just hovering in the black darkness? Is there an artist listening who can draw an artist's interpretation? Could you see the stars behind it or would it be too bright to wash out the stars? Planet Earth would be somewhat hanging overhead, and if this was sunrise, then the Earth would be looking like a crescent Earth? That indeed would be an interesting artist's impression.
An observer on the Moon would always see stars in the sky, day or night.
Armstrong answers about stars. “We were never able to see stars from the lunar surface or on the daylight side of the Moon without looking through the optics."
Of course not. They were looking through highly attenuating glass and had no effective way to shield themselves from glare. Lots of stars are bright enough to stimulate photopic vision, and those will certainly be visible to someone on the Moon who isn't wearing dark glasses. Probably even without blocking the sunlit surroundings.
Chris

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neufer
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Re: APOD: Sunrise at Copernicus Crater (2019 May 30)

Post by neufer » Fri May 31, 2019 2:16 am

Chris Peterson wrote:
Thu May 30, 2019 1:51 pm
neufer wrote:
Thu May 30, 2019 1:36 pm
Chris Peterson wrote:
Thu May 30, 2019 12:37 pm

An observer on the Moon would always see stars in the sky, day or night.
Armstrong answers about stars.

We were never able to see stars from the lunar surface or on the daylight side of the Moon without looking through the optics."
Of course not. They were looking through highly attenuating glass and had no effective way to shield themselves from glare. Lots of stars are bright enough to stimulate photopic vision, and those will certainly be visible to someone on the Moon who isn't wearing dark glasses. Probably even without blocking the sunlit surroundings.
Armstrong was an observer on the Moon...hence:

an observer on the Moon would NOT always see stars in the sky, day or night.
Art Neuendorffer