Cassini/Huygens Mission Update Thread

[backspace]

translated: since we hit that dust speck at 37,500 mph it is now PART of the Lens, Filter or Optic... <img src="/images/icons/smile.gif" />

 

[fangsheath]

Since the posts from the night of orbit insertion were lost, I would like to begin my return to the forums by reiterating my congratulations to the JPL engineers on another wonderful success. Cassini/Huygens has performed virtually flawlessly and will continue to give us fabulous reams of data on the LOR and its many satellites. And again, what a year for planetary exploration!

 

[commander_keen]

I cant wait til Huygens finally decends into Titan's atompshere. We may have so many of our questions to where life began answered or (more likely) it will leave us with more question! <br /><br />

 

[Leovinus]

<i> South Pole on Saturn<br />July 12, 2004<br /><br />Details observed in Saturn’s south polar region demonstrate that this area is far from featureless. Lighter colored clouds dot the entire region, which is dominated by a central, sharply-defined circular feature. Movie sequences in which these features are captured and followed will allow wind speeds in the polar region to be measured.<br /><br />This image was taken with the Cassini spacecraft’s narrow angle camera on May 20, 2004, from a distance of 22 million kilometers (13.7 million miles) from Saturn through a filter centered at 750 nanometers. The image scale is 131 kilometers (81 miles) per pixel. Contrast in the image was enhanced and magnified to aid visibility. </i> <div class="Discussion_UserSignature"> </div>

 

[aaron38]

Now that I'm resurected I can ask a question that's been bugging me for the last few weeks.<br /><br />What is the general consensus of the board regarding liquid on Titan's surface in light of recent observations. It seems like the most recent data is putting a damper on the hopes of surface liquid.<br /><br />If it is there, shouldn't Cassini be able to see it by now?<br />

 

[Leovinus]

I'll withhold my judgement until the closer flybys. <div class="Discussion_UserSignature"> </div>

 

[Swampcat]

Below is a RGB composite of Saturn's southern polar region using raw images taken from approximately 8 million kilometers away on June 18: <div class="Discussion_UserSignature"> <font size="3" color="#ff9900"><p><font size="1" color="#993300"><strong><em>------------------------------------------------------------------- </em></strong></font></p><p><font size="1" color="#993300"><strong><em>"I hold it that a little rebellion now and then is a good thing, and as necessary in the political world as storms in the physical. Unsuccessful rebellions, indeed, generally establish the encroachments on the rights of the people which have produced them. An observation of this truth should render honest republican governors so mild in their punishment of rebellions as not to discourage them too much. It is a medicine necessary for the sound health of government."</em></strong></font></p><p><font size="1" color="#993300"><strong>Thomas Jefferson</strong></font></p></font> </div>

 

[centsworth_II]

<i>"What is the general consensus of the board regarding liquid on Titan's surface in light of recent observations."</i><br /><br />Watching the press briefing after the first Titan flyby, I remember one of the team saying that they were expecting (hoping) to see very bright reflections from liquid ocean or sea surfaces. He said roughness of the surface (waves) could reduce the reflectivity, but I got the impression that he felt that the images from that flyby showed no signs of large bodies of (open) liquid.<br /><br />Of course, that leaves open the possibility of smaller bodies of liquid, or ice-covered oceans.<br /><br />I can't wait for the October flyby! <br /><br /> <div class="Discussion_UserSignature"> </div>

 

[fangsheath]

I don't think the recent flyby unambiguously ruled out large areas of surface liquid. It certainly didn't rule out smaller ones (on the order of many square miles).

 

[SpaceKiwi]

I think the language coming out of the mission managers seems generally more cautious (less optimistic?) than earlier times. I have to say it deflated me a little to hear their comments. Never say never, of course, but the odds seem to have shifted slightly against it now. <div class="Discussion_UserSignature"> <p><em><font size="2" color="#ff0000">Who is this superhero?  Henry, the mild-mannered janitor ... could be!</font></em></p><p><em><font size="2">-------------------------------------------------------------------------------------------</font></em></p><p><font size="5">Bring Back The Black!</font></p> </div>

 

[CalliArcale]

There actually hasn't been a really close Titan encounter yet; the first one is set for October, and that's when we'll start getting really serious data on the subject. Right now, it looks like it could go either way. As has been said before, absence of evidence is not evidence of absence, so who knows? We'll have to wait until Cassini gets closer.<br /><br />Arecibo did detect a very smooth surface on Titan, but not with enough precision to be really sure exactly where it was, or whether it was liquid or just a very smooth solid. Frankly, I'd be interested either way, because a very smooth solid is rather peculiar and should be evidence of a world that is very geologically active. <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>

 

[centsworth_II]

From a detailed paper that AlexBlackwell gave a link to (but I unfortunately lost when SDC went down):<br /><br /><i>"If Huygens lands in liquid, [its] instruments will measure the liquid's properties while the probe floats for a few minutes. If Huygens lands in liquid ethane it will not be able to return data for very long, because the extremely low temperature of this liquid would prevent the batteries from operating.... <br />...[F]rom Titan's surface, [Huygens] will be able to [send data] for a maximum of about 30 minutes, when the probe's battery power is expected to run out and the Cassini orbiter disappears over the probe's horizon."</i><br /><br /><br />So, Huygens can suffer hypothermia just as an arctic explorer falling overboard from his research vessel would.<br /><br />It looks like a good news/bad news situation.<br /><br />The good news: Huyges lands in an ocean and can directly analyse the composition.<br />The bad news: There're only 3 or 4 minutes to do it in. Also, pictures probably would not be very good.<br /><br />Or.... The bad(?) news: Huygens lands on solid ground.<br />The good news: Up to 30 minutes of data collection, including pictures which may be very good.<br /><br />Given these choices, I think I'd choose landing on solid ground. The ideal case would be for the probe to see and analyze remotely a body (or bodies) of liquid on the way down and then land safe and sound on solid ground to continue data collection as long as possible. <div class="Discussion_UserSignature"> </div>

 

[yurkin]

The shore.<br /><br />That would be the best spot. Seeing the ethane waves crash on a rock ice beach. There would be plenty of opportunities to directly measure the ocean when ever a wave came in close enough to the side of Huygens before flowing back. But we'd have to get really lucky.<br />

 

[centsworth_II]

<i>"But we'd have to get really lucky."</i><br /><br />You never know....<br />Hey, they hit a hole-in-one with Opportunity. <div class="Discussion_UserSignature"> </div>

 

[hansolo0]

This is cool that they can record those sounds....but, how do they record sound in a vacuum?<BR /> Also, how was<br />Cassini not destroyed when it is hit by objects at such a great velocity (even dust particles)?

 

[scottcarlin]

When is the next press briefing?<br /><br />

 

[decepticon]

Some New images of Iapetus where taken yesterday.<br />2 Very big craters are visible.

 

[alexblackwell]

<i>There is nothing to talk about right now. The spacecraft is out of communication since it and Saturn are to close to the line of sight to the sun until about July 17.</i><br /><br />I don't know where you're getting your information but this is erroneous. The first solar conjunction period of the tour, defined as when the Earth-Sun-spacecraft angle is 3 degrees or less, lasted from July 4-11, 2004. Full communications have been re-established. <br /><br />For those playing along at home, the other solar conjunction periods for the primary mission are: July 20-26, 2005; August 4-10, 2006; and August 18-24, 2007.<br />

 

[scottb50]

Then we should get a lot of great pictures. What I have seen have shown a lot of detail. Hopefully the October flyby of Titan will we a lot more revealing. <div class="Discussion_UserSignature"> </div>

 

[decepticon]

And on this pass the RADAR instrument should be used!<br /><br />Does anyone know for sure?

 

[Swampcat]

This color image of Iapetus was put together using the IR1, GRN & UV3 filters of Cassini's narrow angle camera. The raw images were taken 07/13/2004 from a distance of approx. 2.5 million kilometers. Some processing was done. <div class="Discussion_UserSignature"> <font size="3" color="#ff9900"><p><font size="1" color="#993300"><strong><em>------------------------------------------------------------------- </em></strong></font></p><p><font size="1" color="#993300"><strong><em>"I hold it that a little rebellion now and then is a good thing, and as necessary in the political world as storms in the physical. Unsuccessful rebellions, indeed, generally establish the encroachments on the rights of the people which have produced them. An observation of this truth should render honest republican governors so mild in their punishment of rebellions as not to discourage them too much. It is a medicine necessary for the sound health of government."</em></strong></font></p><p><font size="1" color="#993300"><strong>Thomas Jefferson</strong></font></p></font> </div>

 

[decepticon]

Nice. I tried to match that large crater with the old voyager maps. Looks like this is in the area not seen buy voyager.

 

[fangsheath]

If I interpret the website correctly, this first orbit is a very eccentric one and will take some time to complete. As is often the case with NASA and JPL websites, I find navigation difficult and answers to simple questions cumbersome to obtain. When is the next perigee?

 

[najab]

><i>When is the next perigee?</i><p>Never, it was a one-way trip. <img src="/images/icons/tongue.gif" /> It's a good question though when the next perichrone(sp?) is.</p>

 

[volcanopele2]

"And on this pass the RADAR instrument should be used!<br /><br />Does anyone know for sure?"<br /><br />Yep, the RADAR instrument will be used on an area north of the "H".