Cassini/Huygens Mission Update Thread

[centsworth_II]

<i>"Do we need to revise down our expectations for the Huygens probe surface pictures?"</i><br /><br />There is a light, 20 watts, I believe, that will turn on as Huygens approaches touchdown. This should allow for lit images of the surface. I think another reason, possibly the main one, for the light is for spectrometry of the surface just before touchdown. I don't know how useful the light will be after touchdown. I suppose it will depend on what type of surface Huygens lands and it's final orientation. <div class="Discussion_UserSignature"> </div>

 

[mooware]

I wonder how much of the sky Saturn would take up on Titan? Must be a heck of a sight. (Yes, I know provided you could see through the haze)<br /><br />

 

[Leovinus]

<i>Cassini continues to uncover new wonders within the Saturn system with its discovery of two new moons orbiting between Mimas and Enceladus.<br /><br />This movie shows the tiny "worldlet," temporarily dubbed S/2004 S2, as it makes its way around the planet. A white box frames the moon's location in the image. The image is part of a sequence specifically designed to search for new moons in the inner saturnian system. The image has not been cleaned of imaging artifacts but has been greatly enhanced in contrast to increase visibility. Consequently, the background scattered light from the nearby rings, as well as many cosmic ray hits and noise patterns, are clearly apparent.<br /><br />The size of S/2004 S2 is estimated to be 4 kilometers (about 2.5 miles) across. Because the moon is small and not resolved it appears as a faint point of light just barely visible above the background.<br /><br />The image was taken on June 1, 2004, aat a distance of 16.5 million kilometers (10.3 million miles) from Saturn. The image scale is approximately 100 kilometers (62 miles) per pixel. The view was taken looking upward from Cassini's southern vantage point beneath the ring plane.<br /><br />The movie consists of two segments: The first covers about 10 degrees of the moon's orbit around Saturn on the left side of the planet, followed by an 80-degree gap, and then another revolution of approximately 30 degrees on the right side. The movie is made up of 28 frames acquired over a period of nine-and-one-quarter hours. The overexposed object seen orbiting Saturn is Enceladus.<br /><br />The moon appears to circle the planet at roughly 211,000 kilometers (131,000 miles). More precise orbit sizes and shapes, as well as any tilt the orbits might have relative to Saturn's ring plane, will require the acquisition of future imaging observations by the Cassini cameras. </i> <br /><br />ANIMATED GIF <div class="Discussion_UserSignature"> </div>

 

[pr0ject0ri0n]

Where have all my posts gone? Hi Leo. Any idea what is happening? An explanation would be much appreciated at this point. It is rather unpleasant to spend useful time writing up responses to other members here only to see those messages nuked the very next day. Is it now Space.com policy to let mods play with the board and mess up threads? If I have in any way violated the rules please advise in what fashion and if possible provide evidence. I have better things to do than play games like this. I do not believe I have done anything deserving of this treatment. Anybody else here getting bullied?

 

[jubal]

Interesting... I would like hear about this first before becoming even remotely involved with this board at all... I've seen arbitrary excercise of control tear up several really good online communities and real world friendships.<br /><br />BTW... does anyone have or know where I can find detailed trajectory info about the multiple grav-boost orbit that was used to assist Cassini to its destination? I'd like to set up a sim for my baby brother and this info would be really helpful.

 

[alokmohan]

Saturn world has two more moons.Exciting ,cassini is doing very well.

 

[crowing]

With all the new moons they keep finding around jupiter,it doesn't surprise me that they will find some new objects-moons circling this gas monster!!

 

[Leovinus]

<i>This Cassini spacecraft wide angle camera view shows a half-lit Saturn, with two dark storms rolling through its southern hemisphere. The image was taken in visible red light on July 19, 2004, at a distance of 6.2 million kilometers (3.9 million miles) from Saturn.<br /><br />The image scale is 366 kilometers (227miles) per pixel. Contrast was slightly enhanced to bring out features in the atmosphere. </i> <div class="Discussion_UserSignature"> </div>

 

[Leovinus]

I think that just about every picture they post has had "contrast enhanced to bring out details". Saturn is pretty boring unless they do this I guess. <div class="Discussion_UserSignature"> </div>

 

[alokmohan]

Saturn excites .In one wayweall knew but when repeated it agitates.

 

[crowing]

I think you're right about that leo!<br />Just giving it a little "tweek",makes for a much better picture,and hey we're still looking at the real saturn aren't we.<br /><br />Good pictures though leo,even if they are "tweeked"!!

 

[Leovinus]

<i>This Cassini spacecraft narrow angle camera view of Saturn's southern polar region shows interesting details in the swirling boundaries between cloud bands. Two faint spots are visible at right, north and south of the boundary of the dark polar collar. The dark spot at the bottom of the image marks the planet's south pole.<br /><br />The image was taken on July 19, 2004, at a distance of 6.2 million kilometers (3.9 million miles) from Saturn, through a filter which lets infrared light pass through. The image scale is 36 kilometers (22 miles) per pixel. Contrast was slightly enhanced to bring out features in the atmosphere. </i> <div class="Discussion_UserSignature"> </div>

 

[Leovinus]

<i>This ultraviolet view shows wavy cloud bands near Saturn's south polar region. Though the region has some visible features, strong contrast between light and dark cloud bands is notably absent, as are bright and dark spots.<br /><br />The eye is drawn to a bright wedge near the lower-left limb (apparent edge) of the planet. That wedge falls in a latitude band that borders a darker latitude band a little closer to the pole. Viewing the limb of the planet in ultraviolet light allows scientists to study the high part of the atmosphere (the stratosphere). Scientists can discern from this image that the stratosphere in this latitude band is relatively pure hydrogen and helium and contains very little of the stratospheric haze that causes darkening closer to the pole.<br /><br />This view was taken with the Cassini spacecraft narrow angle camera on July 21, 2004, at a distance of 6.4 million kilometers (4 million miles) from Saturn. The image scale is 38 kilometers (23 miles) per pixel. The image was taken using a spectral filter centered at 298 nanometers, and reveals different details in the gas giant's atmosphere than those seen in longer wavelengths. Contrast was slightly enhanced to bring out features in the atmosphere. </i> <div class="Discussion_UserSignature"> </div>

 

[mah_fl]

My name is on the Cassini disk.

 

[Leovinus]

<i>With just a bit of detail visible on its lit hemisphere, Tethys was imaged by Cassini on July 20, 2004. A round feature, likely a large crater, can be seen near the boundary where day and night meet, at the bottom of the image. Dark markings are visible near the top.<br /><br />The image was taken in visible light, with the Cassini spacecraft narrow angle camera from a distance of 6.1 million kilometers (3.8 million miles) from Tethys, and at a Sun-Tethys-spacecraft, or phase angle of 92 degrees. The image scale is 37 kilometers (23 miles) per pixel. The image has been magnified by a factor of four to aid visibility. </i> <div class="Discussion_UserSignature"> </div>

 

[larper]

Cassini apoapsis must be coming up pretty soon. Anyone have an exact time and date on that? <div class="Discussion_UserSignature"> <p><strong><font color="#ff0000">Vote </font><font color="#3366ff">Libertarian</font></strong></p> </div>

 

[Leovinus]

Take a look at this graphic. It looks like the orbit is topping out. <div class="Discussion_UserSignature"> </div>

 

[larper]

Yeah, I go there about once a day. I was wondering if someone had the exact day and possibly time it will occur. <div class="Discussion_UserSignature"> <p><strong><font color="#ff0000">Vote </font><font color="#3366ff">Libertarian</font></strong></p> </div>

 

[jimblewit]

There's a pretty complete description of event times at http://caps.space.swri.edu/caps/Tour_Info/Documents/MP_N_qrg.pdf which includes the recently successful Periapsis Raise Manouevre on 23 August at 17:00 followed by the first apoapsis on 27 August at 12:38, both times in SCET, which I believe is Summer Central European Time. <br /><br />CORRECTION: Space Craft Event Time (thanks for pointing that out)

 

[Aetius]

Are you sure that isn't Space Craft Event Time, as expressed in Universal Time Coordinated? I could easily be wrong.

 

[najab]

><i>...and the last planned pressurized burn in the four-year tour...</i><p>To anyone who knows - does this mean that the main propulsion system is going to be inerted?</p>

 

[Leovinus]

<i>An interesting curl in the boundary of a dark polar collar, an area where the bright and dark regions of the atmosphere meet, is visible in this view of Saturn's southern polar region.<br /><br />The image was taken with the Cassini spacecraft narrow angle camera on July 21, 2004, from a distance of 6.4 million kilometers (4 million miles) from Saturn, through a filter sensitive to wavelengths of infrared light. The image scale is 38 kilometers (24 miles) per pixel. Contrast was slightly enhanced to bring out features in the atmosphere. </i> <div class="Discussion_UserSignature"> </div>

 

[jimblewit]

aetius<br /><br />You're right; SCET is space craft event time, as opposed to earth receive time, all measured in universal time. My mistake arose from misreading the ESA site. Here's an explanation of times from NASA:<br /><br />http://saturn.jpl.nasa.gov/operations/saturn-time.cfm

 

[Leovinus]

<i>Encircled in purple stratospheric haze, Titan appears as a softly glowing sphere in this colorized image taken one day after Cassini's first flyby of that moon.<br /><br />This image shows two thin haze layers. The outer haze layer is detached and appears to float high in the atmosphere. Because of its thinness, the high haze layer is best seen at the moon's limb.<br /><br />The image was taken using a spectral filter sensitive to wavelengths of ultraviolet light centered at 338 nanometers. The image has been falsely colored: The globe of Titan retains the pale orange hue our eyes usually see, and both the main atmospheric haze and the thin detached layer have been brightened and given a purple color to enhance their visibility.<br /><br />The best possible observations of the detached layer are made in ultraviolet light because the small haze particles which populate this part of Titan's upper atmosphere scatter short wavelengths more efficiently than longer visible or infrared wavelengths.<br /><br />Images like this one reveal some of the key steps in the formation and evolution of Titan's haze. The process is thought to begin in the high atmosphere, at altitudes above 400 kilometers (250 miles), where ultraviolet light breaks down methane and nitrogen molecules. The products are believed to react to form more complex organic molecules containing carbon, hydrogen and nitrogen that can combine to form the very small particles seen as haze. The bottom of the detached haze layer is a few hundred kilometers above the surface and is about 120 kilometers (75 miles) thick.<br /><br />The image was taken with the narrow angle camera on July 3, 2004, from a distance of about 789,000 kilometers (491,000 miles) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 114 degrees. The image scale is 4.7 kilometers (2.9 miles) per pixel. </i> <div class="Discussion_UserSignature"> </div>

 

[Leovinus]

<i>Wavy bands of clouds near Saturn's south pole dominate this ultraviolet image from the Cassini spacecraft. A bright wedge is visible near the lower left limb (apparent edge) of the planet. That wedge falls in a latitude band that borders a darker latitude band a little closer to the pole.<br /><br />Viewing the limb of the planet in ultraviolet light allows researchers to sample the high part of the atmosphere (the stratosphere). Imaging scientists can discern from this image that the stratosphere in this latitude band is relatively pure hydrogen and helium and contains very little stratospheric haze, which causes darkening closer to the pole.<br /><br />The image was taken on July 22, 2004, from a distance of 6.7 million kilometers (4.1 million miles) from Saturn. The image scale is 79 kilometers (49 miles) per pixel. Contrast was slightly enhanced to bring out features in the atmosphere. </i> <div class="Discussion_UserSignature"> </div>