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Unmanned Spaceflight.com _ Jupiter _ OPAG May 2006 recommendations are out

Posted by: BruceMoomaw Jun 12 2006, 03:50 PM

http://www.lpi.usra.edu/opag/may_06_meeting/agenda.pdf

(I wasn't quite sure where to put this, so here it is in the "Jupiter" section.) The actual presentations aren't on the site quite yet (Fran Bergenal tells me they will be shortly), although the meeting agenda is. OPAG will also be releasing an official exploration "Pathways" document within another week or two.

The main conclusions to be drawn from the report are that Europa is still first priority, a Titan mission must be Flagship-class and should include both an orbiter and "a balloon/aerobot/probe", and discussions of possible Enceladus missions are just starting to get underway.

Posted by: RNeuhaus Jun 13 2006, 03:06 AM

The meeting was already held a month ago. "OPAG Meeting May 4-5, 2006 Westin Hotel 191 North Los Robles Pasadena, CA" I hope that the final findings and comments will be releasing soon. Hope you will catch it and put it on this topic.

Rodolfo

Posted by: elakdawalla Jun 13 2006, 06:08 PM

The final findings and comments were released a couple of days ago. See
http://www.planetary.org/blog/article/00000605/

--Emily

Posted by: RNeuhaus Jun 13 2006, 06:29 PM

QUOTE (elakdawalla @ Jun 13 2006, 01:08 PM) *
The final findings and comments were released a couple of days ago. See
http://www.planetary.org/blog/article/00000605/

--Emily

Interesting reports. Thanks to Emily for the pointing. smile.gif

Rodolfo

Posted by: ljk4-1 Jun 13 2006, 06:40 PM

NASA Outer Planets Assessment Group (OPAG) Meeting Report May 4-5th 2006

http://www.spaceref.com/news/viewsr.nl.html?pid=20986

"The Outer Planets Assessment Group is a NASA-supported forum for
scientists and engineers to discuss exploration of the outer solar system
and to enhance communication between community and NASA. The meeting
of the Outer Planets Assessment Group held at the Westin Hotel, Pasadena,
CA 4-5th, 2005 was attended by ~80 people."


-- Spaceward Bound program in Atacama Desert

http://www.spaceref.com/news/viewpr.nl.html?pid=20071

"What are seven NASA Explorer School teachers doing in the Atacama desert in
Chile? They are studying side-by-side with NASA scientists who search for life in
extreme environments, closely approximating what they expect to find on other
planets. Why the Atacama -- an inhospitable, seemingly lifeless, sun drenched spot
that is probably the driest place on Earth?"

Posted by: Analyst Jun 20 2006, 06:10 PM

Bruce is not here anymore and nobody has discussed this OPAC meeting yet (at least I have not found a thread about it).

http://www.lpi.usra.edu/opag/may_06_meeting/presentations/cooper_1.pdf presentation discusses one possible future of remote sensing on planatary spacecraft, e.g. in the Jupiter system. MIDAS is only a concept by LM (but hardware has been built). It could combine the functions of Cassini’s remote sensing platform and much more into one single piece of equipment with much more capability and adaptibilty. With about the same mass and power restrictions. Very interesting.

My guess: This has some heritage in spy satellites, rather flying or at least concepts. The capabilities match: area imaging at lower resolution, special points with maximum resolution, all in different wavelengths. But this is not the point.

This instrument is something you (only can) develop for a flagship mission and then other missions can use it too. Like Cassini pioneered solid state recorders, or Ka band use or 1024x1024 pixel radiation tolerant CCDs. Its something for a Europa (or Ganymede) orbiter.

What do you think?

Analyst

Posted by: elakdawalla Jun 20 2006, 06:21 PM

MIDAS was presented at that OPAG meeting. It came across very much as a sales pitch for what indeed sounds like an astoundingly capable instrument. But any time anyone in the audience tried to ask a question, the answer was basically "I can't answer that question." Heritage from spy satellites indeed. The response from the audience seemed to be that it sounds nice but that no scientist would trust an instrument if they don't know how it works, and that information didn't seem to be forthcoming.

--Emily

Posted by: nprev Jun 21 2006, 12:12 AM

Hmm...certainly such restrictions would make integration & testing much more difficult. Still, it might not pay to look a gift horse in the mouth. Did anyone ask if legacy SEIT data for this instrument would be provided?

Posted by: Mariner9 Jun 21 2006, 07:52 PM

The Ganymede Observer presentation was interesting. What kind of cost structure were they imagining? Apparently radiation hardened electronics isn't as big an issue as it would be for Europa, and perhaps the fuel requirment to break into Ganymede orbit a bit smaller.... but still, I would think this would be outside a New Frontiers mission scope, and someplace in the Small Flagship range.

And we've seen how well Flagships have done in the budget lately.

Posted by: JRehling Jun 21 2006, 08:26 PM

QUOTE (Mariner9 @ Jun 21 2006, 12:52 PM) *
The Ganymede Observer presentation was interesting. What kind of cost structure were they imagining? Apparently radiation hardened electronics isn't as big an issue as it would be for Europa, and perhaps the fuel requirment to break into Ganymede orbit a bit smaller.... but still, I would think this would be outside a New Frontiers mission scope, and someplace in the Small Flagship range.

And we've seen how well Flagships have done in the budget lately.


Imagine the next 30 years' outer solar system missions in terms of their total budget, expressed in 100 of some unit (which would be tens of millions of current dollars).

Now with the relative levels of interest in Europa, Titan, Enceladus, and the atmospheres of the giant planets, how many of those 100 units will Ganymede get? Let's say the four previous goals get about 20 each, leaving 20 for all remaining goals. Ganymede's not going to get ALL of the rest of the money -- probably not so many as 10 of the 100 units.

Now count how many Flagship/NF missions there will likely be in 30 years, and see if 10 units buys you one.

In a nutshell, Ganymede is not possibly going to get a dedicated mission. It might get a good look-at with a Europa mission, and/or other flybys of craft using Jupiter for gravity assists.

Posted by: Analyst Jun 22 2006, 08:06 AM

You miss the point. In the MIDAS presentation Ganymede itself is not the target, it's the vantage point to study the Jupiter system, e.g. Io, Europa, Callisto and Jupiter itself. And the way to Ganymede gives you some flybys on other moons too.

Analyst

Posted by: JRehling Jun 22 2006, 07:09 PM

QUOTE (Analyst @ Jun 22 2006, 01:06 AM) *
You miss the point. In the MIDAS presentation Ganymede itself is not the target, it's the vantage point to study the Jupiter system, e.g. Io, Europa, Callisto and Jupiter itself. And the way to Ganymede gives you some flybys on other moons too.

Analyst


I'd certainly say Ganymede is overwhelmingly the primary target. Otherwise, they wouldn't spend fuel tying the thing down into Ganymede orbit, which heavily constrains future approaches to the other bodies in the jovian system. The spec of 1 cm/pixel at Ganymede (overflies in every orbit) vs. 100m/pixel at Europa (one encounter per week... always showing the same hemisphere of Europa at highest resolution). You mention Io, but the presentation doesn't in any way mention Io as a goal. I am reminded of an early Hubble release that snapped a picture of Venus and mentioned (this from the PR department) that Hubble could track the weather on other planets... but it had not as of the last time I'd checked taken ANOTHER picture of Venus in the ten years following that release. So much for tracking the weather.

Unlike Venus (and Jupiter and to an extent Io), Europa and Callisto have no time-varying phenomena, so there's really no point in this craft making ongoing observations of those satellites over many years. Once it gets into its final orbit, it could scan the near sides of Europa and Callisto once, scan the far sides once (which for Callisto, would be pointlessly far) and then never observe them again. Io is time-varying but is, again, not mentioned in the presentation. And a Jupiter weather satellite role isn't mentioned in the presentation either (again, it would be a waste to put it into Ganymede orbit if that's what you wanted; a bigger telescope and a lower perijove would both be preferable to that huge shot of fuel for putting it into Ganymede orbit). No, this would be mainly a Ganymede observer doubling as a jovian system comsat. I'm not sure what would require a comsat there, since a craft can't land on Jupiter, can't last long on Io or near Europa, and might as well be its own comsat anywhere else. Maybe if we had a long-life subice lander/submarine at Europa, a comsat would be crucial, but that's far off. (And how useful would it be to have a comsat that doesn't approach Europa except every seven days -- and not VERY closely then?) Really, this mission would have to justify itself as a Ganymede orbiter. And that's not going to happen in the next half-century unless some additional (JIMO, but realistic) considerations sweeten the pot.

Posted by: Mariner9 Jun 22 2006, 09:56 PM

I agree that Ganymede is not likely to be a target for a Flagship class mission in the near future, which is why I raised the question about the cost.

In fact, unless congress overrides NASA's current (aka Griffin's) plan, then the most hope I have in the near future is the New Frontiers AO in 2008. If someone can manage to propose a realistic design for a 3-axis stabalized Jupiter orbiter (preferably with RTGs), I think some type of Galileo-2 type tour would address a lot of scientific goals in the Jovian system. In particular, Io would benefit enormously from additional imagining (especially hi-res color). I think an Io Observer multiple fly-by mission would be justifiable merely on the Io results, but then add in flybys of Europa, and possibly Thebe and Amalthea for good measure, and you've got a real good return on investment.

I know I've made this argument before, but I look back at Viking, Voyager, NEAR, Lunar Prospector, and always remember that all of those were missions which were down-scoped from the original concept.

Loosing the Europa Orbiter is a blow, but there have got to be some some affordable missions that could recover a lot of the lost data.

New Horizons 2, converted to a Jupiter Orbiter? Maybe with a somewhat altered instrument package?

Posted by: The Messenger Jun 23 2006, 04:27 AM

QUOTE (elakdawalla @ Jun 20 2006, 12:21 PM) *
The response from the audience seemed to be that it sounds nice but that no scientist would trust an instrument if they don't know how it works, and that information didn't seem to be forthcoming.

???

Any physcist worth his salt will have any and all black boxes disassembled and reverse engineer the minute the warrenty and property narcs leave the building...we get in trouble for this all the time - we even drill out those funny screws on the microwave ovens smile.gif

Posted by: mchan Jun 23 2006, 05:35 AM

That's assuming you get to keep or even touch the box. They could just provide it as a black box with a programming spec. You get to tell it to do things in the spec and get results, but you don't know what it does to get those results.

Even if you get to open up the box, it would be a lot of work to reverse engineer algorithms that are implemented in an ASIC or custom processor.

Posted by: Analyst Jun 23 2006, 06:56 AM

QUOTE (mchan @ Jun 23 2006, 05:35 AM) *
That's assuming you get to keep or even touch the box. They could just provide it as a black box with a programming spec. You get to tell it to do things in the spec and get results, but you don't know what it does to get those results.


You can't interpret the results in a scientific way if you don't really know how the instrument works. You must know every piece to calibrate it etc. And think about an in flight anomaly. There may be a work around, but you don't know about it. No way. Better built your own instrument you know completely.

If the military wants to have it's toys exclusively, it has to pay for it by itself. In an ideal world they would share, but thats not the way the world turns these days. There are terrorists behind every planet and moon. Funny thing is: With enough money (flagship mission) the scientific community (in several countries) can build instruments with capabilities like MIDAS. Someday they will do so and money has been spent twice or more to reinvent the wheel. I don't even want to talk about ITAR again.

About the Ganymede orbiter: You are right, JRehling. Maybe there is an advantage in terms of lower radiation with this kind of mission compared to a Galileo like mission? But why spent this much fuel. You don't have close flybys of the other moons anymore. But in my defence: The presentation talked about Ganymede being an ideal vantage point. But heh, its a salesman presentation.

Analyst

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