Comments and questions about the
APOD on the main view screen.
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APOD Robot
- Otto Posterman
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by APOD Robot » Sat Aug 08, 2020 4:08 am
Crescent Saturn
Explanation: From Earth, Saturn never shows a crescent phase. But when viewed from a spacecraft the
majestic giant planet can show just a sunlit slice. This
image of crescent Saturn in natural color was taken by the robotic
Cassini spacecraft in 2007. It captures
Saturn's rings from the side of the ring plane opposite the Sun -- the
unilluminated side -- another vista not visible from Earth. Visible are
subtle colors of
cloud bands, the complex shadows of the rings on the planet, and the
shadow of the planet on the rings. The moons
Mimas, at 2 o'clock, and
Janus 4 o'clock, can be seen as specks of light, but the real challenge is to find
Pandora (8 o'clock). From Earth, Saturn's disk is nearly full now and
opposite the Sun. Along with bright fellow giant planet Jupiter it
rises in the early evening.
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orin stepanek
- Plutopian
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by orin stepanek » Sat Aug 08, 2020 11:17 am
CrescentSaturn_cassini_1080.jpg
Beautiful; even a little eerie looking!

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Orin
Smile today; tomorrow's another day!
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WWW
Post
by WWW » Sat Aug 08, 2020 5:45 pm
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Joe Stieber
- Science Officer
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- Location: Maple Shade, NJ
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by Joe Stieber » Sat Aug 08, 2020 6:47 pm
I wonder why the APOD folks don't clearly identify the weekend image replay as an encore presentation (no problem with that; they need a day off too). Every week we have someone seemingly surprised to find it's a recycled picture. The EPOD (Earth Science Picture of the Day) folks do a good job of this, for example, their picture today...
https://epod.usra.edu/blog/2020/08/enco ... -find.html
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Ann
- 4725 Å
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by Ann » Sat Aug 08, 2020 7:01 pm
orin stepanek wrote: ↑Sat Aug 08, 2020 11:17 am
CrescentSaturn_cassini_1080.jpg
Beautiful; even a little eerie looking!
Looks otherworldly, doesn't it?
Ann
Color Commentator
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Grizzly
- Asternaut
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by Grizzly » Sat Aug 08, 2020 7:01 pm
APOD Robot wrote: ↑Sat Aug 08, 2020 4:08 am
From Earth, Saturn's disk is nearly full now
From Earth, isn't Saturn
always a disk?
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johnnydeep
- Captain
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by johnnydeep » Sat Aug 08, 2020 9:18 pm
Grizzly wrote: ↑Sat Aug 08, 2020 7:01 pm
APOD Robot wrote: ↑Sat Aug 08, 2020 4:08 am
From Earth, Saturn's disk is nearly full now
From Earth, isn't Saturn
always a disk?
I think it's always at least gibbous, but not always completely full.
--
"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."
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johnnydeep
- Captain
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by johnnydeep » Sat Aug 08, 2020 9:21 pm
Well, the image is the same, but the text is not.
--
"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."
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johnnydeep
- Captain
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by johnnydeep » Sat Aug 08, 2020 9:25 pm
Took me quite a while to find Pandora. Had to increase the brightness of my display to the max! This image would have benefited from a mouse-over that pointed out where the moons were.
--
"To B̬̻̋̚o̞̮̚̚l̘̲̀᷾d̫͓᷅ͩḷ̯᷁ͮȳ͙᷊͠ Go......Beyond The F͇̤i̙̖e̤̟l̡͓d͈̹s̙͚ We Know."
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DonB312
- Ensign
- Posts: 31
- Joined: Wed Mar 08, 2006 9:38 pm
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by DonB312 » Sun Aug 09, 2020 1:30 am
johnnydeep wrote: ↑Sat Aug 08, 2020 9:25 pm
Took me quite a while to find Pandora. Had to increase the brightness of my display to the max! This image would have benefited from a mouse-over that pointed out where the moons were.
For those with NVidia video cards, there is a setting that can really help get a much better image. Right-click on the Windows desktop, then click "NVIDIA Control Panel". Select "Change resolution" from the list on the left side. Now scroll down to the section titled "Apply the following settings" and find the "Output dynamic range" setting. It usually defaults to "Limited". If you change that setting to "Full" then click the Apply button it will keep the video card from clipping the dynamic range (the detail in the dark and white areas). This makes a very noticeable improvement (at least for me).
I don't know if that setting is available when using the NVidia drivers that come with Windows or if you have to have the drivers from the NVidia web site. But if you find the setting it is easy to try and if you don't like the results it is easy to switch it back to "Limited'.
Oh, and I agree that a mouseover on the image would have been nice. But it's still an awesome image.
Don
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Boomer12k
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by Boomer12k » Sun Aug 09, 2020 3:32 am
Always a great view... my shot of Saturn from the other week... a great object no matter the distance.
Taken with minimal exposure with my Zwo Color Planetary camera and Celestron Evolution 6", around 150 frames stacked and sharpened up in RegiStax 6.
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orin stepanek
- Plutopian
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by orin stepanek » Sun Aug 09, 2020 12:01 pm
Ann wrote: ↑Sat Aug 08, 2020 7:01 pm
orin stepanek wrote: ↑Sat Aug 08, 2020 11:17 am
CrescentSaturn_cassini_1080.jpg
Beautiful; even a little eerie looking!
Looks otherworldly, doesn't it?
Ann
Good description Ann! 🪐
Orin
Smile today; tomorrow's another day!
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neufer
- Vacationer at Tralfamadore
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Post
by neufer » Sun Aug 09, 2020 5:50 pm
DonB312 wrote: ↑Sun Aug 09, 2020 1:30 amjohnnydeep wrote: ↑Sat Aug 08, 2020 9:25 pm
Took me quite a while to find Pandora. Had to increase the brightness of my display to the max! This image would have benefited from a mouse-over that pointed out where the moons were.
For those with NVidia video cards, there is a setting that can really help get a much better image. Right-click on the Windows desktop, then click "NVIDIA Control Panel". Select "Change resolution" from the list on the left side. Now scroll down to the section titled "Apply the following settings" and find the "Output dynamic range" setting. It usually defaults to "Limited". If you change that setting to "Full" then click the Apply button it will keep the video card from clipping the dynamic range (the detail in the dark and white areas). This makes a very noticeable improvement (at least for me).
Alternatively, just look in
the box.
https://en.wikipedia.org/wiki/Pandora_(moon) wrote:
<<Pandora is an inner satellite of Saturn. It was discovered in 1980 from photos taken by the Voyager 1 probe, and was provisionally designated S/1980 S 26. In late 1985 it was officially named after Pandora from Greek mythology. It is also designated Saturn XVII.
Pandora was thought to be an outer shepherd satellite of the F Ring. However, recent studies indicate that it does not play such a role, and that only Prometheus, the inner shepherd, contributes to the confinement of the narrow ring. It is more heavily cratered than nearby Prometheus, and has at least two large craters 30 kilometres in diameter. The majority of craters on Pandora are shallow as a result of being filled with debris. Ridges and grooves are also present on moon's surface.
The orbit of Pandora appears to be chaotic, as a consequence of a series of four 118:121 mean-motion resonances with Prometheus. The most appreciable changes in their orbits occur approximately every 6.2 years, when the periapsis of Pandora lines up with the apoapsis of Prometheus and the moons approach to within about 1,400 kilometres. Pandora also has a 3:2 mean-motion resonance with Mimas.
From its very low density and relatively high albedo, it seems likely that Pandora is a very porous icy body. There is much uncertainty in these values, however, so this remains to be confirmed.>>
Art Neuendorffer