Wrong. When Huygens was launched the expected duration of relay from the surface was FOUR...repeat FOUR minutes. A mirror would have been extra mass. Double resolution wasn't possible with CCD's sensitive enough to do the job when the camera was designed - and would have halved quartered the number of images that could have been sent given the bandwidth available.

Sorry - you just do not understand the complexities of the engineering involved to make such bold, swiping criticism of

Incidentally - the camera on Huygens was an American instrument. Nothing to do with the NAC on Rosetta (so how or why you decided to make that connection I do not know) - and the reason the RAC has LED's on PHX is because that is what it needs to do its job.

I would very strongly urge you to not make further comment - as to be blunt - you don't know what you're talking about.

FWIW, the MSSS proposal for Huygens had considerably higher resolution than DISR. It would have used a custom framing CCD for the descent imaging below the cloud deck. The fact that DISR used one CCD for everything and fiber-optic bundles to feed light from different optics was pretty constraining.

That said, the post did have a lot of misconceptions. We certainly made no specific provisions for landed ops in our proposal, since even surviving the landing wasn't (IIRC) in the baseline.

Since when has that been a constraint on this forum?

How would the number of images returned compare to the DISR proposal, given the same bandwidth? What compression would have been used - wavelets or DCT? Would some "devious" methods have been used - such as performing flatfielding onboard before compression to ensure data bits are allocated on actual image details?

Last, but perhaps a touchy question, why was the DISR proposal selected?

I don't recall what the total number of bits was supposed to be in the AO, nor do I know what DISR proposed and what their actual data return looked like relative to their proposal. I do know that the number of bits ultimately returned was supposed to be 2x what it actually was because of the Cassini commanding screwup.

I think we could have figured out a way to return some better imagery (onboard autonomy to pick good images from bad could be part of it), perhaps at the cost of multispectral coverage, but obviously this is just idle speculation.

I have no insight into why one proposal was selected over another. If I had to guess, I would suspect our proposal didn't seem very technically mature and perhaps somewhat risky, given that our only other hardware effort at the time (MOC1; this was 1990) had yet to fly.

One seemingly zero-cost way to improve the DISR return would have been to have some subset of the post-landing imagery be uncompressed. I would qualify that "zero" with the reminder that any added *anything* you put into software carries some cost and risk. (As the failure to receive the other channel demonstrates.) But no one would doubt that having *any* full-resolution images from the surface would trump having dozens that are identical at sub-optimal resolution.

However, suggesting that a mirror with moving parts be added is another matter. I couldn't say how the pros and cons and risk balance, but it sure would involve risk of significant data loss if the moving parts failed.

Also, I doubt if the science return of a panorama would be equal to the "aesthetics" return. The cameras were after all quite close to the surface. Maybe there was a monolith in the opposite direction, but there's no reason to believe that there would have been anything unlike what was seen as it was. Not much chance of seeing into the middle distance.

Balloon - Rover - It can be both!!!!!
Admittedly, I have a soft spot for this maybe Mars mission - but might be well repurposed for Titan if the uplink to Earth could be solved. That is if it won't stick in the goo....

One way to keep it from sticking in the goo would be to keep it out of the goo altogether -- I'm sure there's plenty of non-gooey terrain.

Of course, my preference is for a liquid-craft -- maybe a sailboat on one of the north polar lakes, or -- and this would be really cool if it could be done -- a riverboat, gliding down one of Titan's many channels (if you can find one that's continuously wet, that is).

Maybe one could combine both: a balloon tethered to a liquidcraft, acting as a sail and pulling the craft along behind it, while also carrying higher-altitude instruments.

The obvious objection is that the craft is likely to snag on something, leaving your balloon stationary and your craft useless... but one can dream!

I know - Titan for all it's oddity, feels more like a real* world of sci fi and fantasy. Immediately recognizable and yet very alien at the same time. The prospect of sailing, floating, roving Titan seems so fantastic but so easily pictured, with a great pale ringed Saturn filling the sky. It's hard to let engineering interfere with that imaginary vision!


* By this I mean no disrespect to the other fine planets, satellites, dwarves and bodies of our fair neighborhood. But as one raised on green dancing girls, wonderful, desiccated Mars is no longer a haven of sci fi fantasy daydreams and has entered the realm of the actual and hopelessly scientific. **

**By this I mean no disrespect to the fine science done by the Saturn Titan team. Plenty of real science there, I know.

This might be another place where the EO-1 software would be applicable.

http://eo1.gsfc.nasa.gov/new/extended/sensorWeb/ase.html

You'd try to take perhaps 100x as many pictures as you could transmit, and let the software choose the 1% most interesting ones to send back.

--Greg