Monday, April 18, 2005

T5 Raw Images

T05 Raw images have started to trickle into the JPL Raw images page. Still waiting for more, but here are the early highlights:
UPDATE 04/18/2005 10:30am: CICLOPS has posted some additional raw images on their website:


Anonymous Ben Short said...

I just discovered your blog and am pleased to find someone who is interested in Titan. I am a retired geologist with 50 years of experience in observing earth landforms and find our neighbors in space very interesting.
Just as a side note, I contacted ESA about the Titan lander and asked why it didn't have a wind powered generator so that the batteries could be recharged thereby providing extended viewing.

I got no response.


4/17/2005 08:32:00 PM  
Anonymous Anonymous said...

Can you imagine "wind powered generator" in -180 degrees C? Even if it was technically possible, Huygens was primarily an atmospheric problem - the landing was a bonus.

4/18/2005 07:43:00 AM  
Blogger Bruce Moomaw said...

Well, actually, there is a gentle breeze of several km/hour on Titan. A better way to do it, though, would be the way that's already been suggested for Venus missions: install a VERTICAL windmill so that the batteries are recharged by the air blowing past the probe on its way down. Since they're suggesting this for a planet with a surface temperature of +480 C, it would hardly be difficult to design it for a world at -170 C.

But the reason they didn't do it on Huygens is, as Anonymous said, that Huygens was designed to be an atmospheric probe -- its landing survival was strictly optional and so they didn't feel it justifiable to spend too much money or payload weight on post-landing meaasurements. This fact is somewhat concealed by the "Surface Science Package" they stuck on it at the last minute, mostly just to provide Britain with a slice of the pie. Every sensor in the SSP was scientifically useless on a non-liquid surface except for the impact-shock sensors (which are the only ones the US National Academy of Sciences recommended for it in 1992) -- and even if it had landed in liquid, every remaining sensor except for the echo sounder and the wave sensor were designed to try and provide "data on the composition of the liquid", which they could have done much better by just including a heated sampling tube with a feed to Huygens' GCMS.

In fact, I think Huygens' biggest design mistake was not to attach a heated core tube to the shaft of Huygens' penetrometer. This would have provided tremendously more information on Titan's surface composition than the SSP sensors could, especially if it landed on semi-solid surface where the SSP was useless -- which, as it turned out, it did. One can also think of a few more post-landing gadgets that might perhaps have been worthwhile even given the extreme uncertainty that it would survive landing: an anemometer, a precipitation sensor, a horizontally tilting mirror to give the SLI camera some panoramic capability after landing... But while I would have put some of these items on it rather than the SSP, let me repeat that anything Huygens got after landing was strictly gravy. If it had hit a genuinely solid surface, there is an excellent chance it wouldn't have survived at all, and its team was well aware of that from the start.

4/18/2005 09:10:00 AM  
Anonymous Pioneer said...

Another factor was the Cassini orbiter was only able to listen to Huygens for a few hours before going out of range. Even if Huygens was able to generate power from the wind, Cassini would not have been able to pick up the signal again for another month or so. The extreme cold would have gotten to Huygens by then.

4/18/2005 01:41:00 PM  
Blogger Bruce Moomaw said...

Yeah, I'd completely forgotten about the obvious point raised by "Pioneer". (Indeed, Huygens was still going strong pwoer-wise when Cassini finally moved out of its radio range.) One other factor: after the first few minutes, there really wouldn't have been that much to be gained by keeping it going -- the only additional benefits would have been protracted surface weather measurements and the observation of any visible changes on the surface (drifting clouds, tricking streams, etc.) Simply not enough to be worth the trouble.

Now, the next Titan mission -- which is very likely to be mobile, with the odds being that it ill be a travelling abllon or blimp capable of multiple landings -- will of course be a different matter. Given our near-total uncertainty until now as to the basic nature of Titan's surface, there have been a surprising number of design studies on a possible "Titan Explorer". One of the more detailed can be found at .

4/18/2005 08:37:00 PM  
Anonymous Gsnorgathon said...

For an estimated price (to NASA) of $680 million? I don't think so... But it would be terrifically cool.

4/19/2005 04:12:00 PM  
Blogger Bruce Moomaw said...

I don't believe that cost figure, either. But here's an exclusive from my upcoming article on the first meeting of NASA's Solar System Strategic Roadmap Committee:

NASA is now leaning toward trying to make its planetary exploration more flexible than the original plan set forth by the 2003 Decadal Survey, by creating a new class of "Intermediate" missions which would probably be between $700 million (the cost cap for New Frontiers) and about $1.5 billion. It will do so by splitting up some of the really super-expensive "Flagship" missions suggested by the Decadal Survey into two or more smaller separate missions (such as perhaps splitting off the Neptune orbiter from a separate Neptune flyby mission carrying several entry probes), and by trying to downscale some of the others with only a modest loss of science. And one possible move of the latter sort would be to remove the orbiter part from the Titan Explorer, leaving just the aerobot vehicle, which would communicate at high speed with Earth even without a relay orbiter by utilzing the new huge arrays of interlinked ground antennas (such as the One Hectare Telescope and the Square Kilometer Array) that will be springing up on Earth in the next decade. There would of course be a science loss -- but this scaled-down mission could probably also be flown within the Intermediate budget, which the full Titan orbiter-aerobot mission cannot be.

4/20/2005 03:10:00 AM  
Blogger Craig Sanders said...

Jason... found your site last week. Good stuff. Thanks!!!

I am intrigued by the streaky splotches seen north of the upper arm of the 'H'. The nitrogen geysers on Triton, as imaged by Voyager 2, looked the same at these image resolutions.

Would the haze in the atmosphere obscure any sunlit highlighting of methane 'steam' going high in the sky?

Would CIRS or VIMS be able to detect 'hotspots' here?


4/20/2005 11:22:00 AM  
Blogger Jason said...

Certainly those streaks have become my new research interest. It is dangerous to compare these to the Triton plume deposits since the vent pressure on Triton can be quite small and a plume would develop, on Titan, the vent pressure would have to be much larger to overcome the atmospheric pressure.

VIMS might detect something, but it would have to be at their 5 micron band given the presumed temperature of the vent.

4/20/2005 01:07:00 PM  

Post a Comment

<< Home