Starship Asterisk*

[quote=illEez post_id=328961 time=1675683586]
Do we have any audio, or a way of getting some, from these worlds and moons we visit
[/quote]
"In space no one can hear you scream."

Do we have any audio, or a way of getting some, from these worlds and moons we visit

[quote=Avalon post_id=328956 time=1675653883]
Any explanation for the many craters at the ice moon's "north" polar region? Is the side we are seeing in the image gravitationally locked with Saturn itself?
[/quote]

The question is not why we see so many craters at Enceladus' north polar region, but why we see so few craters on much of the rest of Enceladus. Because it is extremely normal for the rocky moons of Saturn to have many craters.


[float=left][img3="Dione, cratered moon of Saturn. Credit: NASA - http://photojournal.jpl.nasa.gov/catalog/PIA09861"]https://upload.wikimedia.org/wikipedia/commons/d/d0/Dione_in_natural_light_%28cropped%29.jpg[/img3][/float][float=right][img3="Mimas, extremely cratered moon of Saturn. Credit: NASA / JPL-Caltech / Space Science Institute"]https://upload.wikimedia.org/wikipedia/commons/thumb/b/bc/Mimas_Cassini.jpg/1024px-Mimas_Cassini.jpg[/img3][/float]
[clear][/clear]


Rocky and icy moons of Saturn have so many craters because there are so many large and small boulders flying about around Saturn, and the moons constantly get hit. But much of Enceladus has very few craters, because Enceladus is renewing much of its surface by spewing out plumes of water ice, which cover up most of the craters.


[float=left][img3="The south pole of Enceladus. Geysers spray water from many locations along the 'tiger stripes'. Image Credit: NASA/JPL/SSI"]https://upload.wikimedia.org/wikipedia/commons/e/e6/Enceladus_geysers_June_2009.jpg[/img3][/float][float=right][img3="Cassini's view of the four 'tiger stripes' of Enceladus. The plumes can't be seen from this angle and this illumination. Credit: NASA/JPL/Space Science Institute"]https://upload.wikimedia.org/wikipedia/commons/0/09/Enceladus_Tiger_Stripes_Up_Close_PIA06247.jpg[/img3][/float]
[clear][/clear]



The plumes come from the so called "tiger stripes" near the south pole of Enceladus. That is why it is mostly the south polar region of Enceladus that is almost free of craters.


[float=left][img3="The plumes of Enceladus create their own ring around Saturn, the E-ring. Credit: NASA/JPL-Caltech"]https://utahforge.com/wp-content/uploads/2021/06/Picture2.png[/img3][/float][float=right][img3="The outermost blue ring around Saturn has been created by Enceladus. It is blue for basically the same reason as why the Earth's sky is blue. Credit: NASA/JPL-Caltech/SSI"]https://upload.wikimedia.org/wikipedia/commons/thumb/b/b6/PIA17172_Saturn_eclipse_mosaic_bright_crop.jpg/1920px-PIA17172_Saturn_eclipse_mosaic_bright_crop.jpg[/img3][/float]
[clear][/clear]


Ann

Any explanation for the many craters at the ice moon's "north" polar region? Is the side we are seeing in the image gravitationally locked with Saturn itself?

[quote=MarkBour post_id=328941 time=1675578475 user_id=141361]
What an incredible shot. Cassini was the greatest photographer -- the Ansel Adams of the NASA planetary space missions.
[/quote]
+1 8-) :lol2:

[quote=illEez post_id=328942 time=1675580843]
The long thin crack(?) near the edge on the upper left, from about the 11 o'clock position running down towards the 9 o'clock position looks peculiar, almost a perfect line from our perspective.

I'm assuming a sub-ice slush be more likely than a liquid ocean, possibly dragged about tidally by Saturn?
[/quote]

A slush can only exist in a narrow temperature range. Underneath the ice is almost certainly liquid water, well above freezing.

Icy moon Enceladus must have a water beneath, great & wonderful!

[quote=illEez post_id=328942 time=1675580843]
The long thin crack(?) near the edge on the upper left, from about the 11 o'clock position running down towards the 9 o'clock position looks peculiar, almost a perfect line from our perspective.

I'm assuming a sub-ice slush be more likely than a liquid ocean, possibly dragged about tidally by Saturn?

Beautiful image
[/quote]

You can see the straight lines here straight on.

https://solarsystem.nasa.gov/resources/2391/enceladus-3d-model/

There are actually two thin lines, one running to the north and the other a bit to the left running to the south.

There are also a few unexplained objects I can wonder how they formed. Like there is one large channel running more or less horizontal to the left of these mentioned lines, but there are two large ridges crossing it vertically. Looks like an unmistakable x cross. Now how did that form?

"The long thin crack(?) near the edge on the upper left, from about the 11 o'clock position running down towards the 9 o'clock position looks peculiar, almost a perfect line from our perspective."

...and the lines either side of it around the 10 o'clock position look like they could have been connected at one time?

What do you think; just a line of sight effect, or visible evidence of a huge movement of mass, like plates sliding across each other?

The long thin crack(?) near the edge on the upper left, from about the 11 o'clock position running down towards the 9 o'clock position looks peculiar, almost a perfect line from our perspective.

I'm assuming a sub-ice slush be more likely than a liquid ocean, possibly dragged about tidally by Saturn?

Beautiful image

What an incredible shot. Cassini was the greatest photographer -- the Ansel Adams of the NASA planetary space missions.

I wonder about the structure of the canyon and the ridges in the image. I wonder if somehow their formation is able to be predicted by forces acting on Enceladus. That just maybe, with a detailed analysis, one could actually show that a large crack should form where Labtayt Sulci sits. Maybe even that it should have a sort of a river delta structure at one end and a tangled set of ridges at the other end.

Alternatively, perhaps it is all just a random choice from chaotic influences.

[url=https://apod.nasa.gov/apod/ap230205.html] [img]https://apod.nasa.gov/apod/calendar/S_230205.jpg[/img] [size=150]Enceladus by Saturnshine[/size][/url]

[b] Explanation: [/b] This moon is [url=https://en.wikipedia.org/wiki/Planetshine]shining by[/url] the light of its planet. Specifically, a large portion of Enceladus [url=https://www.flickr.com/photos/ugordan/6823818755/]pictured here[/url] is illuminated primarily by sunlight first reflected from the [url=https://solarsystem.nasa.gov/planets/saturn/in-depth/]planet Saturn[/url]. The result is that the normally [url=https://apod.nasa.gov/apod/ap050317.html]snow-white[/url] moon appears in the gold color of [url=https://apod.nasa.gov/apod/ap170829.html]Saturn's cloud tops[/url]. As most of the illumination comes from the image left, a [url=https://en.wikipedia.org/wiki/Labyrinth]labyrinth[/url] of ridges throws notable shadows just to the right of the image center, while the kilometer-deep canyon [url=https://apod.nasa.gov/apod/ap081222.html]Labtayt Sulci[/url] is visible just below. The bright thin crescent on the far right is the only part of [url=https://solarsystem.nasa.gov/moons/saturn-moons/enceladus/in-depth/]Enceladus[/url] directly lit by the Sun. The [url=http://www.flickr.com/photos/ugordan/6823818755/]featured image[/url] was taken in 2011 by the robotic [url=https://solarsystem.nasa.gov/missions/cassini/mission/spacecraft/cassini-orbiter/]Cassini spacecraft[/url] during a close pass by by the [url=https://www.intermountainpet.com/hubfs/Blog_Images/Dogs-tilting-their-heads.jpg]enigmatic[/url] moon. Inspection of the lower left part of this digitally sharpened image reveals [url=https://apod.nasa.gov/apod/ap170416.html]plumes of ice[/url] crystals thought to originate in a [url=https://astrobiology.com/2022/09/new-evidence-for-habitability-in-enceladus-ocean.html]below-surface sea[/url].


[table][tr][td=left][url=https://asterisk.apod.com/discuss_apod.php?date=230204][b]<< Previous APOD[/b][/url][/td] [td=center][url=https://asterisk.apod.com/view_retro.php?date=0205][b]This Day in APOD[/b][/url][/td] [td=right][url=https://asterisk.apod.com/discuss_apod.php?date=230206][b]Next APOD >>[/b][/url][/td][/tr][/table]