Huge News! The fountains of Enceladus

[chew_on_this]

Pics to come!

 

[chew_on_this]

A fine spray of small, icy particles emanating from the warm, geologically unique province surrounding the south pole of Enceladus was observed in a Cassini narrow-angle camera image of the crescent moon taken on January 16, 2005.<br /><br />Taken from a high phase angle of 148 degrees – a viewing geometry in which small particles become much easier to see – the plume of material becomes more apparent in images processed to enhance faint signals. <br /><br />Imaging scientists have measured the light scattered by the plume's particles to determine their abundance and fall-off with height. Though the measurements of particle abundance are more certain within 100 kilometers (60 miles) of the surface, the values measured there are roughly consistent with the abundance of water ice particles made by other Cassini instruments (reported in September, 2005) at altitudes as high as 400 kilometers (250 miles) above the surface.<br /><br />At present, it is not clear if the plume emanating from the south pole arises because of water vapor escaping from warm ice that is exposed to the surface, or because at some depth beneath the surface, the temperatures are hot enough for water to become liquid which then, under pressure, escapes to the surface like a cold Yellowstone geyser. <br /><br />The image at left was taken in visible green light. A dark mask was applied to the moon’s bright limb in order to make the plume feature easier to see.<br /><br />The image at right has been color-coded to make faint signals in the plume more apparent. Images of other satellites (such as Tethys and Mimas) taken in the last 10 months from similar lighting and viewing geometries, and with identical camera parameters as this one, were closely examined in order to demonstrate that the plume towering above Enceladus' south pole is real and not a camera artifact.<br /><br />The images were acquired at a distance of about 209,400 kilometers (130,100 miles) from Enceladus. Image scale is about 1 kilometer (0.6

 

[chew_on_this]

Recent Cassini images of Enceladus at high phase show the fountain-like sources of the fine spray of material that towers above the south polar region of Enceladus. The image was taken looking more or less broadside at the 'tiger stripe' fractures observed in earlier Enceladus images and shows discrete and small-scale plumes above the limb of the moon.<br /><br />The color-coded image at right was processed to enhance faint signals, making contours in the plume of material even more apparent. The greatly enhanced and colorized image shows the enormous extent of the fainter, larger-scale component of the plume.<br /><br />The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Science Mission Directorate, Washington, D.C. The imaging team consists of scientists from the US, England, France, and Germany. The imaging operations center and team lead (Dr. C. Porco) are based at the Space Science Institute in Boulder, Colo.<br /><br />For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.<br /><br />Credit: NASA/JPL/Space Science Institute<br />Released: November 28, 2005 (PIA 07758, 07759)<br />Image/Caption Information <br /><br />Gee whiz, maybe steve can shed some more of his scientific wisdom on this apparent impossibility.

 

[CalliArcale]

AWESOME NEWS!!!<br /><br />This is very very cool! Cryovolcanism on Enceladus! <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[chew_on_this]

I guess Triton isn't the only active icy moon in the outer solar system. Hats off to the Cassini imaging team! From the original e-mail from Carolyn Porco:<br /><br />When, what to our wondering eyes should appear....<br /><br /><br /><br />November 28, 2005<br /><br /><br />Dear Friends and Colleagues,<br /><br />In one of the most thrilling moments we have enjoyed in a mission filled with thrilling moments, fountain-like plumes of small icy particles emanating from the south polar region of Enceladus have been seen in recently acquired Cassini images of the small Saturnian moon.<br /><br />These spectacular images reveal in glorious detail an array of individual jets close to the surface, as well as the enormous and faint<br />plume of material extending far above Enceladus. Not since Voyager's<br />discovery of volcanoes on Jupiter's moon, Io, and geysers on Neptune's moon, Triton, have we seen such fabulous visual evidence of present-day geologic activity in the outer solar system.<br /><br />Visit ...<br /><br /> http://ciclops.org<br /><br /><br />... to see for yourself.<br /><br /><br /><br />Enjoy!<br /><br />Carolyn Porco<br />Cassini Imaging Team Leader<br />Director/CICLOPS<br />Space Science Institute<br />Boulder, CO<br />

 

[telfrow]

To echo Calli...Awesome news! <div class="Discussion_UserSignature"> <strong><font color="#3366ff">Made weak by time and fate, but strong in will to strive, to seek, to find and not to yeild.</font> - <font color="#3366ff"><em>Tennyson</em></font></strong> </div>

 

[bad_drawing]

This is so cool! Further evidence of EPH! *JOKE*<br /><br />I did my daily stop by the jpl sight and my jaw dropped when i saw the pix and info..after trolling through all I could find on the plumes I had to come to SDC message boards to find people who share in the excitement of this! What a mission. Congrats once again to all involved.

 

[silylene old]

Here's a nice picture, composed by Bjorn Johnson to give some perspective on the water jets.<br /><br />I had to repost my post from 8/17/05 back this thread:<br /><br />It is possible the localized temperature on Encelaudus is 300K or even higher. http://uplink.space.com/showflat.php?Cat=&Board=sciastro&Number=151667&page=3&view=collapsed&sb=5&o=0&fpart=9<br /><br /><i>As I understand it, the temperature from the IR measurement is the average temperature measured over the entire measurement area. The 110K may not be the exact temperature of the fissure; actually it's just one knowledgable person's estimate. All we do know is that the average of the area of the hot fissure and the area of the surrounding cold ice surface was found to be 91K. <br /><br />So I will make an estimate too.... <br />If the 5% of the area in the box is occupied by a fissure at a balmy 300K, and the 95% of the area of the box surrounding surface is a frigid 80K, then the average temperature seen by the detector = 0.05*300 + 0.95*80 = 91K. <br /><br />In my estimate, I assumed 5% of the fissure was actually open and shedding heat (this assumption made my numbers look good! Actually I wanted to illustrate that there might actually be some significant heat source if it is small and localized in the center of a cracked ice surface.) </i> <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[silylene old]

And to remind everyone, here was the temperature measurement results from the fissures at the south pole, which I referred to in my above post: <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[yurkin]

Holy smokes.<br /><br />I was expecting to see little geysers like the ones on Triton. Not a huge eruption out of the side of the planet.

 

[CalliArcale]

It really is huge, isn't it? That's what really blows me away here. It even puts the big plumes on Io to shame, if I'm perceiving the relative sizes correctly. Fascinating.<br /><br />And yeah, as has been pointed out, this wasn't entirely a shock. The huge oxygen cloud observed by Cassini a few months ago was a strong sign of this sort of activity. But there's nothing like actually seeing it! <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[jatslo]

I think something that massive would move the moon, or change the orbit, and I believe the water is actually liquid before it freezes in space, similar to a geyser. I hope Titan turns out to be just as exciting, if not, more exciting. Wow!!! To bad we don't have the funds to send 100's of crafts into the cosmos.

 

[jmilsom]

Yes. Amazing, amazing, amazing. We need to send an orbit craft to every moon. If only! Spectacular stuff from Enceladus, and great images from Rhea just a few days ago. <div class="Discussion_UserSignature"> </div>

 

[bonzelite]

this is just amazing stuff. i nearly cannot believe the warmth of the surface areas at the fissures. 5% of one of the boxed areas shown is 300K?! that is actually almost mild weather temperatures on earth. and this body is so far away from the sun. imagine the interior. it must actually be HOT. <br /><br />our outer gas planets' miniature solar systems seem to steal the show again, and again, and again... ---i'm speechless.

 

[igorsboss]

Is there enough material ejected to show up as ring structures?

 

[silylene old]

<font color="yellow">5% of one of the boxed areas shown is 300K?! that is actually almost mild weather temperatures on earth. </font><br /><br />I am speculating this is correct (and it now appears so based on the water 'geysers'). If 5% of the boxed area was 300K, then the boxed area would have the observed average temperature.<br /><br />We need to send another probe with much greater infrared spatial resolution - quickly, before the vent cools down and freezes over again! <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[CalliArcale]

<blockquote><font class="small">In reply to:</font><hr /><p>Is there enough material ejected to show up as ring structures?<p><hr /></p></p></blockquote><br /><br />Meaning a ring around Enceladus? Probably not; remember that Enceladus isn't all that big. These particles are quite possibly ejected at greater than escape velocity. However, it may feed Saturn's ring system. This would be similar to Io's volcanoes feeding Jupiter's delicate dusty rings. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[bad_drawing]

Hi Igorboss,<br /><br />There's some speculation on a similar thread that Enceladus might be the source of the tenous E-ring<br /><br />http://uplink.space.com/showflat.php?Cat=&Board=sciastro&Number=151667&page=0&view=collapsed&sb=5&o=0&fpart=1&vc=1<br /><br />This certainly boosts that argument a bit. Earlier when Cassini flew through and detected the outgassing it aroused suspision, but the new image really shows the large scale of the eruptions (if thats the right term). Sooo fascinating.<br /><br />With some mechanism producing enough pressure to make plumes as impressive as they are, I suspect Silylene is right: the area close to the fissures is likely to be much much warmer then that indicated by the average. I wonder if theres any reasonably accurate way of telling how long this fissure has been active. So many questions! Outstanding stuff.<br /><br />

 

[rlb2]

PIA07759 <div class="Discussion_UserSignature"> Ron Bennett </div>

 

[jatslo]

Looks like the little engine that can; I wonder where it is going. Nice pic!

 

[webscientist]

Excellent news and excellent analysis Silylene!<br />300 k corresponds to 26.85°c or 80.33°F.If those icy particles ejecting from those grooves are really made up of water, that means that a subsurface ocean is possible beneath this icy crust. But, at which depth?This is a large field of speculation for astrobiologists.<br />I'm really surprised that a moon, so small ( 500 km in diameter ) is able to generate so much energy from its interior. It should be a dead world!like our moon.<br />We can now extrapolate to Titan Europa or Triton the lessons from this astonishing news.<br /><br />www.titanexploration.com

 

[toymaker]

What could this mean for other Moons of the similiar type ? Could it indicate that subsurface of Europa is hot enough for life ?

 

[rlb2]

<font color="orange">Looks like the little engine that can; I wonder where it is going.<font color="white"><br /><br />Tantalizing enough to get us working on faster transportation for an eventual human exploratory mission, but in the near future we will have to rely on robotics.<br /><br />The image above is from here:<br /><br />http://www.spaceref.com/news/viewsr.html?pid=18828<br /><br /><br /></font></font> <div class="Discussion_UserSignature"> Ron Bennett </div>

 

[CalliArcale]

Be nice. Just because people are supporting theories contrary to yours does not give you the right to call them names. <div class="Discussion_UserSignature"> <p> </p><p><font color="#666699"><em>"People assume that time is a strict progression of cause to effect, but actually from a non-linear, non-subjective viewpoint it's more like a big ball of wibbly wobbly . . . timey wimey . . . stuff."</em>  -- The Tenth Doctor, "Blink"</font></p> </div>

 

[unlearningthemistakes]

a big news indeed... <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <p>pain is inevitable</p><p>suffering is optional </p> </div>