APOD: Saturn's Moon Pan from Cassini (2017 Mar 13)

Comments and questions about the APOD on the main view screen.
douglas

Re: APOD: Saturn's Moon Pan from Cassini (2017 Mar 13)

Postby douglas » Mon Mar 13, 2017 7:18 pm

Daphnis, bump this up to high magnification, very instructive
https://saturn.jpl.nasa.gov/resources/7589/

"You can also see the vertical waves caused by the moon’s feeble pull. Each wave corresponds to one up-and-down bob of the moon relative to the rings. Eventually, tides from Saturn pull the particles back down, but that takes a while, and the ripples extend for a long way around the ring."
http://www.slate.com/blogs/bad_astronom ... rings.html


"What causes those ripples? The orbit of Daphnis is not a perfect circle, but instead is very slightly elliptical. That means it’s sometimes closer to the inner edge of the Keeler gap, and sometimes closer to the outer one. The change is small, only about nine km, but that’s enough. When it’s closer to one edge it pulls on the ring particles a bit harder, creating the wave.


But there’s more to it. The orbit of Daphnis is also tipped a bit to the ring plane, a mere 0.0036° from being exactly aligned. That means it bobs up and down out of the ring plane by about 17 km. When it does it drags the ring particles at the gap edges as well. Those waves you see in the image go in and out of the gap, but also up and down by a kilometer or so."

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Re: APOD: Saturn's Moon Pan from Cassini (2017 Mar 13)

Postby Astronymus » Mon Mar 13, 2017 9:36 pm

This moon is the weirdest thing.

douglas

Re: APOD: Saturn's Moon Pan from Cassini (2017 Mar 13)

Postby douglas » Mon Mar 13, 2017 11:21 pm

Astronymus wrote:This moon is the weirdest thing.


Its brim appears to indicate it does not tumble.

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Re: APOD: Saturn's Moon Pan from Cassini (2017 Mar 13)

Postby ccnield27@outlook.com » Mon Mar 13, 2017 11:45 pm

that's not Pan. It's Kyle from South Park!

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Re: APOD: Saturn's Moon Pan from Cassini (2017 Mar 13)

Postby Boomer12k » Tue Mar 14, 2017 12:37 am

Ray-Optics wrote:Since Pan orbits in the Encke gap along with an irregular ringlet, a hypothesis for the hat brim occurs to me: It is picking up "snow" from this ringlet along its "equator" of spin. Pan's gravity must be very low, so ring snow could pile high. An overall snow layer may also account for the relatively young-looking surface.


My guess too... like Enceladus ejecting the Ice in the first place... only a matter of time a moon would, or at least MIGHT, pick up a good deal... it is like a planet, clearing out its orbit, it gathers debris. Maybe that is WHY it is the Encke Gap???? It has cleared much of its orbit.

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Re: APOD: Saturn's Moon Pan from Cassini (2017 Mar 13)

Postby neufer » Thu Mar 16, 2017 9:53 pm

.
You’ve met Saturn’s ravioli-shaped moon, Pan.
Now learn how it was discovered.
Art Neuendorffer

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Re: APOD: Saturn's Moon Pan from Cassini (2017 Mar 13)

Postby Ann » Thu Mar 16, 2017 10:58 pm

neufer wrote:.
You’ve met Saturn’s ravioli-shaped moon, Pan.

:chomp:

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Re: APOD: Saturn's Moon Pan from Cassini (2017 Mar 13)

Postby JohnD » Fri Mar 17, 2017 9:12 am

Art's erudition and polytemporalistic tendency (no doubt the result of residence on Tralfamadore) has led him astray.
My reference was not to Bo-peep (Fool, King Lear, Act 1, Scene 4, Page 8) but to Jeremiah 50:6 (qv)
John

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Re: APOD: Saturn's Moon Pan from Cassini (2017 Mar 13)

Postby BDanielMayfield » Fri Mar 17, 2017 11:41 am

JohnD wrote:Art's erudition and polytemporalistic tendency (no doubt the result of residence on Tralfamadore) has led him astray.
My reference was not to Bo-peep (Fool, King Lear, Act 1, Scene 4, Page 8) but to Jeremiah 50:6 (qv)
John


Very nice John. I had to look it up. It fits.

Bruce
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Re: APOD: Saturn's Moon Pan from Cassini (2017 Mar 13)

Postby neufer » Fri Mar 17, 2017 1:01 pm

Click to play embedded YouTube video.
BDanielMayfield wrote:
JohnD wrote:
Art's erudition and polytemporalistic tendency (no doubt the result of residence on Tralfamadore) has led him astray.
My reference was not to Bo-peep (Fool, King Lear, Act 1, Scene 4, Page 8) but to Jeremiah 50:6 (qv)

Very nice John. I had to look it up. It fits.
Art Neuendorffer


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