APOD: Shadows and Plumes Across Enceladus (2014 Aug 04)

[APOD Robot]

Shadows and Plumes Across Enceladus

Explanation: Why does Enceladus have ice plumes? The discovery of jets spewing water vapor and ice was detected by the Saturn-orbiting Cassini spacecraft in 2005. The origin of the water feeding the jets, however, remained a topic of research. A leading hypothesis held that the source might originate from a deep underground sea, but another hypothesis indicated that it might just be ice melted off walls of deep rifts by the moon's tidal flexing and heating. Pictured above, the textured surface of Enceladus is visible in the foreground, while rows of plumes rise from ice fractures in the distance. These jets are made more visible by the Sun angle and the encroaching shadow of night. Recent study of over a hundred images like this -- of geysers crossing Enceladus' South Pole, together with regional heat maps, indicate that these plumes likely originate from a hidden sea, increasing the chance that this frosty globe might be harboring life.

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[Ann]

My favorite moon is at it again! Enceladus is the only moon I know of that has something in common with an elephant and a whale.

Ann

[Nitpicker]

My favorite moon is at it again! Enceladus is the only moon I know of that has something in common with an elephant and a whale.

Ann

I too am an Enceladus lover. But the Earth's moon appears to have the same colour as elephants (and dolphins, which are closely related to whales, but better at surfing.) Or is that irrelephant?

[Boomer12k]

I doubt that it is anything more than Chemically Illuminated bacterial life....but there is always hope in our imaginations.....

I am holding out for 36 Double D. HOT ELF MERMAIDS..... ....but it will probably be...THE GIL MAN....from the Black Lagoon....


:---[===] *

[JuanAustin]

Is it only in certain areas where these geysers are or are they located moon-wide?
They can't be seen in the foreground at all, why would they be so fine and hard to see in the foreground?
Could the rings of Saturn (and Jupiter) be "spent" remnants of moons that were eventually ground away by tidal forces from the inside out then broken up into bits and pieces finally?

[mister T]

Those are not ice plumes, they are the floodlights from an Illuminati/CIA/Halliburton terra-forming/strip mining operation.
They are getting a jump on the colonization and subsequent environmental destruction of mans next home.

[BDanielMayfield]

Is it only in certain areas where these geysers are or are they located moon-wide?

If memory serves these geysers are only found at the poles, maybe just the south pole.

[MadMan]

I was going to ask about the dark moon that was behind the plumes, but then I realized that it was just Enceladus' shadow cast against the plumes.

[Psnarf]

Last time I tried talking to a sea bass, it didn't have much to say. I'd be surprised if there were no extraterrestrial life at all. Bacteria and other single-celled organisms like those found near deep sea vents, that are currently being mined for gold, are possible. Life forms with which we can communicate? Least likely.
--
Obquote:
"Sea bass.
Sea bass run.
Run, run, run. --George Burns over his weekly lunch at the Friars Club.

[hypermetabolic]

The geysers are backlit yet Enceladus is sidelit - is it a montage or is Enceladus lit by Saturn in this photo?

[Ann]

Nitpicker wrote:
irrelephant

Ann

[neufer]

Is it only in certain areas where these geysers are or are they located moon-wide?

---

<<The tiger stripes of Enceladus consist of four sub-parallel, linear depressions in the south polar region of the Saturnian moon. First observed on May 20, 2005 by the Cassini spacecraft's Imaging Science Sub-system (ISS) camera, the features are most notable in lower resolution images by their brightness contrast from the surrounding terrain. Higher resolution observations were obtained by Cassini's various instruments during a close flyby of Enceladus on July 14, 2005. These observations revealed the tiger stripes to be low ridges with a central fracture.

Observations by Cassini during the July 14, 2005 flyby revealed a cryovolcanically active region on Enceladus centered on the tiger stripe region. The CIRS instrument revealed the entire tiger stripe region (south of 70° South latitude) to be warmer than expected if the region were heated solely from sunlight. Higher resolution observations revealed that the hottest material near Enceladus' south pole is located within the tiger stripe fractures. Color temperatures between 113–157 kelvins have been obtained from the CIRS data, significantly warmer than the expected 68 kelvins for this region of Enceladus.

Data from the ISS, Ion and Neutral Mass Spectrometer (INMS), Cosmic Dust Analyser (CDA) and CIRS instruments show that a plume of water vapor and ice, methane, carbon dioxide, and nitrogen emanates from a series of jets located within the tiger stripes. The amount of material within the plume suggests that the plume is generated from a near-surface body of liquid water. Over 100 geysers have been identified on Enceladus.>>

[bystander]

http://asterisk.apod.com/viewtopic.php?t=33691

[Nitpicker]

The geysers are backlit yet Enceladus is sidelit - is it a montage or is Enceladus lit by Saturn in this photo?

Enceladus is sidelit by sunlight reflected off Saturn, methinks.

[DavidLeodis]

In the information brought up through the "Pictured above" link there is an annotated version. In the information about that it stated "In an annotated version of the image, the colored lines represent the projection of Enceladus' shadow on a plane normal to the branch of the Cairo fracture (yellow line), normal to the Baghdad fracture (blue line) and normal to the Damascus fracture (pink line). Post-equinox images like this, clearly showing the different projected locations of the intersection between the shadow and the curtain of jets from each fracture, were useful for scientists in checking the triangulated positions of the geysers...".

That's most interesting, as I would not have otherwise realised that there was any need for an annotated version!

I wonder why the fracture names were so chosen