Unveiling Titan

[alexblackwell]

From the October 2004 issue of <i>Icarus</i>:<br /><br />Fluorescence spectra of Titan tholins: in-situ detection of astrobiologically interesting areas on Titan's surface<br />Robert Hodyss, Gene McDonald, Niladri Sarker, Mark A. Smith, Patricia M. Beauchamp and J. L. Beauchamp<br /><i>Icarus</i> <b>171</b>, 525-530, (2004)<br />Abstract

 

[alexblackwell]

An interesting paper currently in press with <i>Icarus</i>:<br /><br />Reactions of nitriles in ices relevant to Titan, comets, and the interstellar medium: formation of cyanate ion, ketenimines, and isonitriles<br /><i>Icarus</i>, In Press, Corrected Proof, Available online 14 August 2004<br />R.L. Hudson and M.H. Moore<br />Abstract

 

[alexblackwell]

Published online yesterday in the <i>Journal of Geophysical Research-Space Physics</i>:<br /><br />Bolton, Scott J.; Hansen, Candice J.; Matson, Dennis L.; Spilker, Linda J.; Lebreton, Jean-Pierre<br /><b>Cassini/Huygens flyby of the Jovian system</b><br /><i>J. Geophys. Res</i>., Vol. 109, No. A9, A09S01<br />10.1029/2004JA010742<br />30 September 2004<br />Abstract<br />Special Section

 

[alexblackwell]

Some interesting Titan-related abstracts can be found here, here, and here.

 

[alexblackwell]

<i>Interestingly, I understand some of the Huygens crowd are really concerned about, believe it or not, Iapetus. Specifically, they are browbeating Cassini Mission Planning for an accurate value for Iapetus' GM parameter. This has to do with the fact that while Iapetus' mass is too low to give any type of useful gravity assist, it is large enough that the Probe's post-release trajectory is expected to be perturbed before Titan entry, which could affect the landing zone. Note also that Cassini performs a non-targeted flyby of Iapteus on January 1, 2005 (13 days before the Hugyens Probe entry at Titan during Tc).</i><br /><br />To deal with this issue, Cassini Mission Planning (MP) has just released a new tour reference trajectory (041001) that changes the closest approach (C/A) distance for the Rev C non-targeted flyby of Iapetus, which was originally scheduled for January 1, 2005. For those playing along at home, the new values are:<br /><br />Probe C/A 121,128 km on December 31, 2004 at 19:19:55 UTC<br />Orbiter C/A 117,535 km on December 31, 2004 at 19:01:58 UTC<br /><br />As might be expected, this trajectory "tweak" also has a downstream effect on the tour; for example<br /><br />- Tb has been lowered to 1200 km<br />- T3 has been raised to 1577 km<br />- Probe B-plane angle target changed to 167.5º<br />- The times of PTM and ODM have been changed to match new times in CIMS<br /><br />There are other, mostly minor, effects. For example, small deltas of a few tens of kms to some Titan C/A's (<i>e.g</i>., T10 and T12).

 

[alexblackwell]

While waiting for the upcoming Cassini Ta flyby on October 26, 2004, Titanphiles may wish to surf over to the Keck Observatory Titan Monitoring Project.

 

[alokmohan]

Titanophiles.Good ha ha!

 

[alexblackwell]

Cassini Mission Planning (MP) has just released some products for the upcoming Ta flyby on October 26, 2004. First, a Ta flyby movie (~121 Mb), which, unfortunately, is not publicly available. The movie shows the FOVs of the remote sensing pallet instruments throughout the Ta encounter sequence. Secondly, MP produced a document articulating the Ta science goals (quoted below) as well as a detailed Ta timeline.<br /><br />=====================================================================<br /><br />Titan-A Science<br /><br />Titan A will provide the first in-situ sampling of Titan's atmosphere ever. This will contribute significantly to atmospheric model updates necessary to validate the 950 km minimum flyby altitude (and perhaps the Huygens mission profile as well). The sources of this improvement will come primarily from INMS data and AACS attitude control telemetry during the flyby.<br /><br />CAPS will make its first measurements of Titan's upper ionosphere and gather science from Cassini's first crossing through Titan's plasma wake. They will make both ion and electron measurements during the flyby, except for the period from about closest approach –85 to –30 minutes.<br /><br />CIRS will measure the stratospheric temperatures versus pressure (and therefore density), in part to contribute to Huygens mission validation at the altitudes of parachute deployment.<br /><br />ISS will conduct its first medium and high resolution imaging of Titan, including imaging of the Huygens landing site. The cameras will perform distant observations at about 2.7 kilometers per pixel, a full-disk color mosaic at about 2 km/pixel, regional to global mapping of the western bright/dark boundary at 200-600 meters per pixel, and very high resolution imaging of an edge of a bright area at 23-81 meters per pixel.<br /><br />INMS, again, will perform the first ever in situ measurements of Titan's upper atmosphere, to determine the density and composition.<br /><br />MAG will perform a detailed study o

 

[alexblackwell]

Published online today in the journal <i>Radio Science</i>:<br /><br />Pechony, Olga; Price, Colin<br /><b>Schumann resonance parameters calculated with a partially uniform knee model on Earth, Venus, Mars, and Titan</b><br /><i>Radio Sci</i>., Vol. 39, No. 5, RS5007<br />10.1029/2004RS003056<br />09 October 2004<br />Abstract

 

[imran10]

Titan's Strange Prospects<br />SpaceDaily<br />October 15, 2004

 

[imran10]

NASA Announces Cassini Titan Flyby Coverage<br /><br />Saturn's smog-cloaked moon Titan will be examined up close by the Cassini spacecraft next Tuesday. Cassini will fly by Titan at 1,200 kilometers (745 miles). In the close flyby, which is about 250 times closer than its flyby in July, Cassini's radar will be used for first time to image the cloud-shrouded Titan. <br /><br />TELEVISED EVENTS AND PRESS CONFERENCES: <br /><br />Friday, Oct. 22 <br /><br />--Live satellite interviews on NASA TV, 3 to 7 p.m. EDT <br /><br />Monday, Oct. 25 <br /><br />--Listen-and-log-on workshop on Titan science objectives, noon to 1 p.m. EDT. Reporters may attend or participate on line by calling the JPL Media Relations Office at: 818/354- 5011 for attendance or dial-in information. Supporting images and graphics will be posted on the Web at the start of the workshop, at: <br /><br />www.jpl.nasa.gov/media/cassini-102504 <br /><br />Tuesday, Oct. 26 <br /><br />--Live NASA TV commentary on first Titan pictures from the flyby, 9:30 p.m. to 3 a.m. EDT. The program will air in several segments. <br /><br />Wednesday, Oct. 27 <br /><br />--News briefing, quick look at initial images, noon to 1 p.m. EDT <br /><br />--Live satellite interviews on NASA TV, 3 to 7 p.m. EDT <br /><br />Thursday, Oct. 28 <br /><br />-- News briefing, science results, noon to 1 p.m. EDT <br /><br />Friday, Oct. 29 <br /><br />-- Listen-and-log-on news briefing, summary of science findings, noon to 1 p.m. EDT.

 

[imran10]

Cassini RADAR : First Encounter with Titan<br /><br />C. Elachi, Y. Anderson, R. Boehmer, P. Callahan, G. Hamilton, M. Janssen, W. T. K. Johnson, K. Kelleher, R. Lopes, S. Ostro, L. Roth, S. Wall, R. West (JPL), M. Allison (NASA/GISS), C. Wood (PSI), F. Posa (Politecnico di Bari), E. Stofan (Proxemy Research), H. Zebker (Stanford University), R. Lorenz, J. Lunine (LPL, University of Arizona), G. Francescetti (University of Naples), G. Picardi, R. Seu (University of Rome "La Sapienza"), D. Muhleman (California Institute of Technology), P. Encrenaz (DEMIRM/Obs. de Paris), R. Kirk (USGS) <br /><br /><i>Titan's thick, hazy atmosphere poses challenges to optical and near-infrared imaging of its surface, and to studies of surface topography in particular. Cassini therefore carries a sophisticated Ku-band multimode radar, operating with 5 beams generated with Cassini's 4m high-gain antenna. This instrument can be operated only close to Titan will be used on around half of Cassini's Titan encounters. <br /><br />The Cassini TA flyby with Titan on 26 October 2004 has a closest approach altitude of 1200km, and features several RADAR observations. The instrument will perform scatterometry over part of the antisaturn hemisphere of Titan, including the planned Huygens probe landing site on the inbound leg of the flyby. Shortly before closest approach, the Synthetic Aperture Radar (SAR) mapping mode of the instrument will be used to image a small region (~0.5 of the surface at around 40 deg N latitude with a planned resolution of between 0.4 and 2km. Additional observations outbound from Titan include a short altimetry swath, additional scatterometry, and a low-resolution full-disk passive radiometry map. We will present the available results from the initial analysis of the active measurements of this first Titan encounter.</i>

 

[fangsheath]

This flyby will be awesome. Titan is finally giving up its secrets. I feel as much anticipation as I did when Voyager approached Neptune.

 

[imran10]

I can hardly wait! <br /><br />5 days, 3 hours remaining..

 

[decepticon]

I have been looking at the first Titan flyby images very closely and I think that those Bright areas are glaciers!<br /><br />Anyways Thats my Guess as to what they are.<br /><br />Also looking at the Images from the Keck Oberservations, titan may have some massive impact craters.<br /><br />I will post a pic later showing the areas where I see this.

 

[centsworth_II]

The bright areas on Titan...<br /><br /><font color="yellow">"What those areas are will in time be figured out, but are probably atmospheric events."stevehw33 -- </font><br /><br />The pattern of dark and light areas on Titan have remained consistent in both Earth-based telescope images and Cassini images. They are definately not atmosphereic features. They are real ground features. There have been bright clouds seen high over the southern pole of Titan. Other than that, the main atmoshereic feature has been the thick moon-wide haze which blocks any sight of Titan's surface with visable light.<br /><br />That the light and dark areas represent real ground features is not in question. The question is what the features are made of: ices, rocky surface, organic goo.... <div class="Discussion_UserSignature"> </div>

 

[alexblackwell]

<i>Just a few things, Alex, you always use acronyms. Most of us could do that and utterly obfuscate what we are talking about, IMHO.</i><br /><br />True, though I think I have a good track record of clarity in my posts (<i>e.g</i>., spelling out acronyms, providing links, <i>etc</i>.).<br /><br /><i>So, explicate please...</i><br /><br />All of these are instruments on the Cassini Orbiter that will be taking measurements during the Ta flyby. Rather than "explicate," I'll just link to the relevant Cassini web page, which does a far better job than I could.

 

[alexblackwell]

A detailed description (~6.2 Mb PDF) of the upcoming Ta flyby is now available.

 

[CalliArcale]

Thanks! I may be a hopeless nerd for saying this, but I always really enjoy getting the nitty-gritty timelines of these sorts of events. <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>

 

[alexblackwell]

UA's Cassini Scientists Ready for First Close Titan Flyby<br />By Lori Stiles, UANews.org<br />October 25, 2004

 

[alexblackwell]

First Close Encounter of Saturn's Hazy Moon Titan<br />October 25, 2004<br />Jet Propulsion Laboratory

 

[volcanopele2]

And yes, that is me in the first image in that article <img src="/images/icons/smile.gif" />

 

[volcanopele2]

Definitely, many of the equatorial bright areas and dark areas are surface features. However, there are clouds that are scattered throughout the atmosphere, as can be seen in the latest raw images so some bright features are atmospheric features. But the bright features seen in the dark region west of Xanadu and Xanadu have been seen by Cassini since before SOI (just not with this much detail) are surface features. What are they one might ask. I think after tonight we will have a general idea, but like almost all major spacecraft encounters, it will answer a lot of question, but it will raise twice as many <img src="/images/icons/wink.gif" />

 

[yurkin]

Sorry I asked this question in another thread but, does anyone know when the radar mapped data is going to be displayed?

 

[volcanopele2]

It is my understanding that the RADAR team won't even LOOK at their SAR data until tomorrow morning. SAR data takes a lot longer to get from raw data of the spacecraft to something viewable. So rather than slow down the process by trying to look at the noodle-strip, they are going to wait till it is done. So they won't look at it till 7am tomorrow PDT (again that's my recollection) and the press conference tomorrow is at 9am PDT, so it would be cutting it awfully close if they are going to release something tomorrow. There is another press conference scheduled for Thursday and I would expect something from radar then.