[X] My Assistant

[infocat13]

OPAG ( outer planets assement group) meets on November 6th through 7th.I still do not see the agenda posted for this does someone have it?
This the last OPAG meeting before the outerplanet fagship mission downselect decision is made in early 2009.So lets have fun! a poll for wich mission you would pick
to go first.I was going to add a third option and that would have been that DJ and I got Bill gates to pay for the losing candidate from next springs downselect............................................
Decadel surveys and "complex" have lower prioritized Uranus and neptune missions but someday advances in aerobraking and ion propolsion will make possible discovery class outer planets missions so keep up that outer-outerplanets hope up.(the third toungue in cheek option in the poll)


http://www.lpi.usra.edu/opag/

[djellison]

Sorry - I've closed the poll. It's not a productive way to have this debate - experience shows they don't benefit the discussion.

[infocat13]

Sorry - I've closed the poll. It's not a productive way to have this debate - experience shows they don't benefit the discussion.

well doug maybe you could tell me when the agenda for the November meeting might be posted on the OPAG website?
for a meeting only 3 or 4 days away they sure are cuasing alot of nail biting.
I voted for saturn in that a titan lander or "boat" could discover "something wonderful" and that would drive exploration and funding much like the allen hills "discovey" did for mars for decades to come. Jupiter being a surface and radar imaging of Ganeymeade and Europa will tell us more about the charateristics of any subsurfice oceans but would not tell us much about whats under there.of course some the intruments might tell us what the surface colorations are on Europa.
my second reason is one of public relations, Jupiter would be a radiation shortend mission. Saturn will thrill us for another decade and this as mentioned above generates excitment that could losen more funding for well ........Jupiter and the other gas giants.

Opag and complex would say that both missions have compelling scientific value but theres money enough for one and I for one look forward to the AO in the spring.we are in for a candy store of a ride through some nice PDF documents in the next week do I have to wait till the 6th?

[vjkane]

well doug maybe you could tell me when the agenda for the November meeting might be posted on the OPAG website?

I will post a summary at http://futureplanets.blogspot.com/ when the presentations are available. This meeting will get an update on the definition process, but no decision on which mission will fly.

[elakdawalla]

I got the following in an OPAG email...

OPAG Meeting November 6-7, Tempe, AZ

Four Points Sheraton
1333 South Rural Road
Tempe, AZ

Thursday, November 6
8:00 Steering Committee Meeting
8:30 Welcome & PSS report Fran Bagenal (U Colorado)
8:45 HQ Update Jim Green (NASA HQ)
9:45 BREAK
10:00 EJSM EJSM Team
12:00 LUNCH
1:00 TSSM TSSM Team
3:00 BREAK
3:15 Breakouts
4:15 New Frontiers to Neptune Candice Hansen (JPL) & Heidi Hammel (SSI)
4:40 Open Mike/Disburse to Reception

Reception at the Greeley household

Friday, November 7
8:00 Steering Committee Meeting
8:30 Outer Planets program Status Curt Niebur (NASA HQ)
9:30 Cassini Data Usability Claudia Alexander (JPL)
10:00 Science Talk – Adam Showman
10:30 BREAK
10:45 Decadal Survey and Mission Studies Ron Greeley (ASU), Jim Green (NASA HQ)
11:15 Future Missions/Open Mike Bill McKinnon (Washington Univ)
11:45 Actions, Findings, and Logistics Bill McKinnon (Washington Univ)
LUNCH

[infocat13]

I got the following in an OPAG email...

Fantastic!
many thanks
your wonderful!
I see a paper from Hiedi about the neptune mission, may she fly someday! er the spacecraft not the PI
EJSM EJSM VS TSSM TSSM !
and yes of course the final downselect is in Jan 2009
and on friday I see Decadal Survey and Mission Studies it is interesting to observe how this evolves over the decades I use to buy NASA complex and decadel surveys from the government printing office before the age of computers and now that OPAG is online you can see meeting PDF reports back into the past to see the give and take of the science community

[volcanopele]

Downselect is in mid-February, not January.

[infocat13]

Downselect is in mid-February, not January.

great!
Oct 2008 OPAG papers state a hope for a springtime AO but no date set ,but that is assumming we know by then the state of mind of our ESA partners?
but then again NASA has that standby of this mission being a stand alone mission if need be.
Volcanoepele you are hoping for a mission with more volcanoes in your future? the japan and ESA contrabutions will they be targeting your faverite world?

[volcanopele]

The downselect I was referring to was the OPF one (EJSM or TSSM). EJSM will flyby Io 3-5 times before JEO goes into orbit around Europa. So that mission covers at least a little bit of my favorite world. TSSM will of course orbit and land/fly around my second favorite world.

I'm still conflicted between which one I support. I guess TSSM would provide A LOT of info on my second favorite world, then I can hope for an Io mission with the NF AO after this upcoming one. Such a mission would arrive at Jupiter about the time JEO would.

[infocat13]

Unnecessary quote removed - Mod

well come to think of it Titan does have suspected volcanic features I think in the radar images so you are in business and...............may I sell you on a Triton mission? there are Geyser features in the Voyager images so there will be volcanopeles on mission teams for decades to come.
And Ceres may have done some melting early in its history soon we will know
I was referring to OPF as well.Do we downselect with ESA at the same time? I did not realize there where IO flybys as well in the EJSM this must be near and after Jupiter orbit insertion? and a thought.......... the Europa orbiter will impact that world at end of mission but maybe there is possibilty of end of mission scenerios for the japan or ESA orbiters to take a dive towards that sulfer world. Or end of mission for those spacecraft at a trojan asteriod.

OPAG documents are up!

http://www.lpi.usra.edu/opag/nov2008Meetin...ations/EJSM.pdf
http://www.lpi.usra.edu/opag/nov2008Meetin...ations/TSSM.pdf
http://www.lpi.usra.edu/opag/nov2008Meetin...tions/TSSM2.pdf
http://www.lpi.usra.edu/opag/nov2008Meetin...tions/TSSM3.pdf
Solar arrays! Really? Was this incorperated in the ideas submitted in March. I see 5 ASRG to as well.

http://www.lpi.usra.edu/opag/nov2008Meetin...tions/TSSM4.pdf
http://www.lpi.usra.edu/opag/nov2008Meetin...tions/TSSM5.pdf
http://www.lpi.usra.edu/opag/nov2008Meetin...s/nieburOPP.pdf
http://www.lpi.usra.edu/opag/nov2008Meetin...ons/cassini.pdf
http://www.lpi.usra.edu/opag/nov2008Meetin...cadalSurvey.pdf

weeeeeeeeee ! an evening of reading tonight

[Phil Stooke]

Try hitting 'add reply' at the bottom of the page instead of ' " reply ' after the message. (It would be good to remove the ' " reply ' button if it could be done.)

Phil

[Shaka]

What's the difference between "add reply" and "fast reply" ?

[djellison]

Hitting fast reply gives you a limited options way of posting. not smiley icons, no attachments, not extended formatting etc etc
Hitting reply at the bottom of a page is a full new post to that thread
Hitting reply on someone's post is a full new post to that thread with the entire contents of the post you hit reply on, pre-quoted.

The point is - if your post is going under the post you're replying to - you do not need to quote it. That's called inline quoting and it's un-necessary, grows the database, slows down the forum, and generally makes threads unnecessarily lengthy to scroll down.

Doug

[Mariner9]

inline quoting and it's un-necessary

Doug

If you really do want to quote something specific that someone said (perhaps buried quite a few posts back up in the thread somewhere) there is no need to keep the entire quote. Once the edit window comes up, remove everything except the quote tags and the one part of the quote you really want.

If you are not sure you did it correctly, select preview to see how it looks.

[infocat13]

I had a problem with the reply function and edit to an existing post yesterday.....so this is "reply" at bottom of page lets see if it works for me!

http://www.lpi.usra.edu/opag/nov2008Meetin...tions/TSSM3.pdf


Solar arrays! Really? Was this incorperated in the ideas submitted in March or something new?. I see 5 ASRG to as well.
On slide 29 there is end of mission planning but I am confused , are they planning a Titan impact at end of mission ?

[Guest_PhilCo126_*]

http://www.lpi.usra.edu/opag/nov2008Meetin...tions/TSSM3.pdf
Page cannot be found

[jamescanvin]

http://www.lpi.usra.edu/opag/nov2008Meetin...tions/TSSM3.pdf

[infocat13]

http://www.lpi.usra.edu/opag/nov2008Meetin...tions/TSSM3.pdf

The URL seems to work for me indeed the front page of the PDF document shows our Intrepid Saturn explorer with two solar arreys!
I think I will go and look at the March OPAG PDF documents to see how this compares. Are we saving on RTG'S( I think not)
and what would be the trade here? would the wieght of the solar array and its launch costs make up for any savings on supplamenting the RTG's?

[mchan]

The two arrays are part of the SEP stage.

[infocat13]

The two arrays are part of the SEP stage.

Ahhhhhhh!
inner solar system orbit!
the Eveej trajectory!
got it
thanks

[SFJCody]

I'm no chemist, so the following is probably completely wrong, but it seems to me that when this warm plutonium powered machine from our silicate world drops into Kraken Mare it might quickly be wreathed in ethane steam. This might make post splashdown imaging problematic.

[ngunn]

I understood the lake boat would be battery powered and short-lived, like Huygens.

[SFJCody]

I understood the lake boat would be battery powered and short-lived, like Huygens.

Ah, OK. I hope it's well insulated!

[centsworth_II]

This might make post splashdown imaging problematic.

A wet landing will certainly pose lens contamination problems. They probably won't even know what types of contamination to prepare for. Even with a dry landing, the thick atmosphere can carry any number of contaminants onto a lens.

[rlorenz]

A wet landing will certainly pose lens contamination problems. They probably won't even know what types of contamination to prepare for. Even with a dry landing, the thick atmosphere can carry any number of contaminants onto a lens.

Huygens didnt seem to have any issues....

But in any case, imaging isnt a major priority for the TSSM lake lander - it is north polar winter
when it descends, so twilight imaging I guess. For the spectacular vistas, see the montgolfiere

[Mariner9]

A wet landing will certainly pose lens contamination problems.

Fortunately I understand the engineers at ESA have spent a lot of time and research on a solution to this.


It's called a lenscap.



All kidding aside, I would imagine that any contaminents would only spash up on the initial contact with the ocean. After things settle down, it is a comparatively simple matter to jetison the lenscap and be able to take those fabulous photos of ... uh.... well, uh ...

That brings up the next problem.... what exactly would you take pictures of? You think the surface of the ocean looks dull on Earth, imagine a place with lower light levels and virtually no wind gusts.

[nprev]

At the risk of sounding heretical, I would almost trade an imager for a basic underliquid sonar mapping capability...but upon further reflection, nah. We don't know enough about the liquid's composition to design such an instrument (though a depth sounder would be a must-have; the observed transmission properties would set some additional constraints on the material's composition, and I'm assuming that they'll try some sort of chemical analysis).

As for imagery...I vote IR!

[Juramike]

sonar mapping capability...but upon further reflection...

<ouch!>

[nprev]

...how'd I know that Mike would catch that...

[infocat13]

so we do an experiment?
NASA JPL ESA build a engineering flight article and.........................................
emerse it in a liquid ethane/organic carbin mixture make and run experiments with different theorys on turbity

[tty]

As for imagery...I vote IR!

How much IR would there be at that temperature?

[Juramike]

For fine IR spectral analysis, you'd need to bring your own IR source, as in this apparatus (which I refer to as "The Fickle Finger of Fate").

The diagnostic information from the IR bands that you'd get would only give you some functional group types. You'd still not be able to discern exact discrete chemisal structures ("Yup! There are some hydrocarbons in there!")
A better analytical tool would be GC analysis. Even better would be GC-MS.

For actual imaging, I'd be paranoid that a scum/crud/foam layer might extend up from the surface, and you'd be guessing how high up the mast to mount the camera to avoid looking at a bunch of suds. You might have the same problem under the surface as well.

Pure Hexanes and other hydrocarbons should be nice and clear. It is the trace polymers, emulsions, and other gookies that might crud stuff up under the surface - but the trace polymers, emulsions and gookies are exactly the things that might be the most chemically interesting.

-Mike

[rlorenz]

At the risk of sounding heretical, I would almost trade an imager for a basic underliquid sonar mapping capability...but upon further reflection, nah. We don't know enough about the liquid's composition to design such an instrument (though a depth sounder would be a must-have....

speak for yourself.....
Huygens had a depth-sounder which would have worked fine had we not dumped it in a desert.....

We know the speed of sound in liquid hydrocarbons (and the Huygens SSP
instruments were tested in the stuff). Sure, suspended gunk and dissolved goop may influence absorption/
scattering, but that's useful to measure too. I've recently looked at beam-steering sonar for Titan landers -
the difficulty is that the sound speed is high enough that for realistic frequencies the wavelength is long
enough that a beam-steering array needs to have a large physical separation between the radiating elements.

Really need to stream a sonar array behind us as we motor around doing Crazy Ivans in Kraken Mare

[nprev]

...I stand corrected, Ralph! (How about a towed transmitter with a little side-scan sonar receiver a few meters behind it for bottom mapping?)

TTY: IIRC, the best surface imagery's been observed at around 3 microns or so from VIMS? I don't think that's re-radiation from absorbed sunlight--it's probably direct solar illumination/reflection--and since it penetrates the haze & escapes to space more readily than the other bands I'm thinking that it might be the 'brightest' component of sunlight at the surface.

I bet that the liquid hydrocarbons & associated gunk absorb it pretty thoroughly, though; the mares look really, really dark.

[Juramike]

TTY: IIRC, the best surface imagery's been observed at around 3 microns or so from VIMS?

IIRC the best surface imagery is at 3 um from orbit because it has the best trade-off between useful signal and noise in an interesting region in a methane window with lower haze scattering.

Titan's atmospheric hazes really mess with the shorter wavelengths.

Shorter wavelengths (like ISS's 0.93 um and VIMS 1.28 um) have more haze-scattering (more fuzziness) but are brighter, while the longer wavelengths (like 5 um) have less haze-aerosol scattering, but are darker so there's more noise in the signal. (Graphic of Titan windows vs. water ice spectrum here)

-Mike

[vjkane]

Shorter wavelengths (like ISS's 0.93 um and VIMS 1.28 um) have more haze-scattering (more fuzziness) but are brighter, while the longer wavelengths (like 5 um) have less haze-aerosol scattering, but are darker so there's more noise in the signal. (Graphic of Titan windows vs. water ice spectrum here)

-Mike

Between the longer wavelength, atmospheric scatter, and the lack of shadows, imaging Titan is hard. Strategies such as really big cameras (think HiRise on MRO) probably won't work for increasing resolution. The proposed TSSM mission is planning on just 50 m. I work with Landsat 30 m images. This is a tool for characterizing landscapes, not for fine geology. Unfortunately, what makes Titan so interesting -- its atmosphere -- makes it harder to study. It's going to be hard to distinguish albedo features from topographic features without good shadowing.

There is one technical trick that could help. If you have a camera that looks down (nadir) and then offset to either front or back, you can generate stereo images with vertical resolution roughly the same as horizontal. Mars Express' camera does this as does the Terra ASTER camera. The data rate increases since you are taking two sets of images, but the offset image can be in a single color (the ASTER offset band is near IR, for example).

[stevesliva]

Really need to stream a sonar array behind us as we motor around doing Crazy Ivans in Kraken Mare

You expect those Titanian orcas to sneak up on you from behind?

[nprev]

Good point. Might be worth adding a hook and some bait (a nice, juicy ball of tar?) just in case!

The conditions would be ideal for trolling, anyhow; you have to move slowly to do sonar mapping or the image smears out.

[Juramike]

Gee, if we can extend the wireless range of this a few million km, we could get the Titan lake sonar results on our wristwatch.

[hendric]

The data rate increases since you are taking two sets of images, but the offset image can be in a single color (the ASTER offset band is near IR, for example).

There should be quite a bit of correlation between the two images. I think you could use a motion based compression algorithm to minimize the data transmission overhead of that extra image.

[rlorenz]

Between the longer wavelength, atmospheric scatter, and the lack of shadows, imaging Titan is hard. Strategies such as really big cameras (think HiRise on MRO) probably won't work for increasing resolution. The proposed TSSM mission is planning on just 50 m. I work with Landsat 30 m images. This is a tool for characterizing landscapes, not for fine geology. Unfortunately, what makes Titan so interesting -- its atmosphere -- makes it harder to study.

The atmosphere makes it easy to study in-situ, though, permitting the delivery to the surface of instrumentation
far easier than on an airless world. And of course permitting a balloon (or other aerial platform) which
can give you HiRise-resolution imagery...

(btw - people have said 3 microns is the best near-IR wavelength - actually it is 2 microns)

[infocat13]

The Argo PDF document is now up on the OPAG November meeting website


http://www.lpi.usra.edu/opag/nov2008Meetin...ations/argo.pdf


one trajectory option is Jupiter Saturn Neptune/Triton and then a KBO!


whats new? (from March meeting) science coverage of tritan northern hemishere

image triton unseen by voyager

[stevesliva]

Still really interesting, thanks.

On the "cost saving options" slide, it mentions making Jupiter and Saturn "missions of opportunity." Is there really enough runway to do that for Jupiter? Saturn I can believe.

Also interesting are the OPAG requests at the very end-- two of three are infrastructure! Hopefully that's an easier sell in the current economy.

[gpurcell]

Still really interesting, thanks.

On the "cost saving options" slide, it mentions making Jupiter and Saturn "missions of opportunity." Is there really enough runway to do that for Jupiter? Saturn I can believe.

I wonder if that is referring to a revenue-enhancement option rather than a cost-savings option! You've got a bare-bones NF mission under $800M and you also get $50-$100M for the MoO for Jupiter/Saturn...making the whole ball o'wax a $900M mission.