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Posted by: Val Klavans Nov 24 2013, 04:45 AM

Rev199 can be found here: http://www.ciclops.org/view/7726/Rev199

We're finally receiving some good raws from Cassini again! I just put together these three views of Titan, from images snapped by Cassini yesterday (November 22): http://www.flickr.com/photos/valerieklavans/11014534693/

Posted by: titanicrivers Nov 24 2013, 10:27 PM

Beautiful imaging Val ! (and thanks for the link to how you did it!)

Posted by: Ian R Nov 25 2013, 05:28 AM

Great stuff, Val

Here's my attempt to enhance the haze in a RGB composite using the UV channel:

Posted by: titanicrivers Nov 30 2013, 02:26 AM

From the T96 mission overview http://saturn.jpl.nasa.gov/mission/flybys/titan20131201/ "Titan approaches summer solstice. VIMS will also look for specular reflection in an area located to the east of Ara Fluctus, between latitudes 53 N and 48 N and between longitudes 130 W – 163 W. "
I wonder if that should be to the west of Ara Fluctus based on the coordinates given ??? (see IAU map below)

Posted by: titanicrivers Dec 3 2013, 01:32 AM

The T96 flyby is already providing another ‘bonanza’ of North polar lakes on Titan. Two images from Nov 30 2013 taken with the CL1 CB3 filter are shown, one highlighting the intriguing Mackey Lacus, the other showing a panoply of smaller, sharply demarcated lakes. The SAR map http://planetarynames.wr.usgs.gov/images/NP_lakes_low_noboundaries.pdf is used to help identify the lakes.

EDIT: Although I did use the map with names above I still managed to spell Mackay Lacus wrong!

Posted by: titanicrivers Dec 7 2013, 04:13 AM

A closer look at Mackay Lacus show what appears to be a string of small interconnected lakes surrounded by considerable evaporite (see http://www.ciclops.org/view_media/38701/Titans-Northern-Lakes-Salt-Flats )

Posted by: dilo Dec 7 2013, 05:48 AM

Beautiful work, titancrivers!
Looking to these polar maps, I wonder there are so many "white" regions not covered by radar... do someone knows which is actual global coverage and if it will reach 100% of Titan surface before the End of Mission? (Sorry if question is slightly off-topic).

Posted by: elakdawalla Dec 7 2013, 05:05 PM

Radar will never achieve 100% coverage of Titan. Coverage is good near the north pole because it was in the dark for the prime mission, but that didn't limit RADAR work there.

Posted by: Explorer1 Dec 8 2013, 02:48 AM

Yeah, don't expect 95% global coverage in Magellan's style. Flybys necessarily limit how much can be scanned even apart from the limited fuel and time for other instruments to do their work. Filling in every white space is largely academic, like getting the exact poles, etc.
Cassini can only ever do flybys, though I have vague recollections of some talk early in the mission about the possibility of aerocapture into Titan orbit at the end of the main mission, using the main antenna as a sort of heatshield. Dunno if it was anymore plausible than escaping Saturn for Uranus/Neptune/Centaurs....

Posted by: djellison Dec 8 2013, 04:45 AM

None of the above are plausible.

Posted by: Explorer1 Dec 8 2013, 05:20 AM

Yeah, that's pretty much what I figured. There's a few old articles from before the first mission extension, a few journal articles about possible escape trajectories, etc. All academic, given that the real EOM has been settled upon...

Posted by: dilo Dec 8 2013, 06:55 AM

I hope like an aerobrake only, it would be frustrating to orbit around Titan without antenna for radar coverage! cool idea, anyway!

Posted by: nprev Dec 8 2013, 04:56 PM

It's just not gonna happen. Even if this were possible to do the spacecraft would eventually crash onto Titan, and it's not sterilized to PPP standards.

Cassini's EOM will be very similar to that of Galileo.

Posted by: stevesliva Dec 8 2013, 05:44 PM

I recall there was a serious proposal to send Cassini to Uranus, in that someone who writes papers about that sort of thing had worked out the mechanics of it being possible. Though, in all seriousness, the science lost at Saturn meant that was never going to happen.
http://www.sciencedirect.com/science/article/pii/S009457651200149X
http://arc.aiaa.org/doi/abs/10.2514/1.42893?journalCode=jsr

Posted by: 0101Morpheus Dec 9 2013, 05:16 PM

Uranus does strike me best destination to send Cassini to if that action had been approved. And it is almost tempting visit a planet we haven't been to in 27 years.

The main issue is escaping Saturn's gravity well, which would be really, really, hard. I remember reading somewhere that Cassini might have just enough fuel to do it but it would take several years. So put together several years of doing nothing but burning fuel and doing gravity assists to escape Saturn then fly toward Uranus, which would take considerably longer to get to than Voyager 2 since this is no longer the 1970's. And who knows what condition Cassini would be in when it arrived...yeah. It's better to stay at Saturn.

I am looking forward to riskier maneuvers with the spacecraft, like flying through the ring plane and I would kill to get another flyby of Iapetus, which is IMO the most mysterious of Saturn's moons now.

Figuratively of course.

Posted by: NickF Dec 9 2013, 06:12 PM

The Acta Astronautica paper linked by Steve Silva makes fascinating reading.

The optimal cruise time for a Saturn-Uranus transfer seems to be 26 years, with a Saturn departure date of Feb 8, 2020. 42 years to Neptune, departing Mar 21, 2017. (Worth noting that these are flyby- or impact missions). All unlikely to happen, of course, but fun to think about.

Posted by: djellison Dec 9 2013, 06:39 PM

Not unlikley to happen. IMPOSSIBLE. There is no where near enough fuel onboard to even entertain the idea.

Posted by: 0101Morpheus Dec 9 2013, 06:51 PM

Can we settle for a flyby of Iapetus then?

Posted by: Explorer1 Dec 9 2013, 08:08 PM

No; March 2015 is the last distant encounter, at almost a million kilometers!
The mission planners have settled on a plan for the next few years and they're not going to change it without good reason.

Posted by: stevesliva Dec 9 2013, 08:27 PM

That's what I was trying to get at... the propellant necessary would mean sacrificing an incredible final tour and the proximal orbits--let's not forget that this will be unique for Cassini-- in favor of getting whatever instruments still work to another planet in several decades. For only a fly-by. All that said, neat stuff.

Posted by: Explorer1 Dec 12 2013, 07:58 PM

Back on the topic of radar coverage, here's a new radar map of the north polar seas:
http://photojournal.jpl.nasa.gov/catalog/PIA17655

A few big blank spaces left at around 65 N, 55 W and the pole itself, but if the infrared already shows nothing there, not much point filling them in, is there?

Posted by: elakdawalla Dec 12 2013, 09:10 PM

You have no idea how hard they tried to fit another Iapetus flyby into the XXM tour. They wanted it badly, but while they could do lots of amazing things with very limited fuel, another Iapetus flyby would come at too high cost of other great science, so they had to give up the idea.