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Unmanned Spaceflight.com _ Cometary and Asteroid Missions _ Discovery Program 2006 and Missions Of Opportunity

Posted by: AlexBlackwell Jan 3 2006, 10:19 PM

I'm not sure exactly which forum this fits in but NASA has just released the AO for Discovery Program 2006 and Missions of Opportunity. See the http://discovery.larc.nasa.gov/discovery/ for more details. Click on the "Discovery AO" link to download the PDF.

Posted by: djellison Jan 3 2006, 11:28 PM

All the documentation says there are guides to the current status of Stardust and DI at the library
http://discovery.larc.nasa.gov/discovery/dpl.html

but I cant find them ohmy.gif

Doug

Posted by: AlexBlackwell Jan 4 2006, 12:23 AM

QUOTE (djellison @ Jan 3 2006, 11:28 PM)
All the documentation says there are guides to the current status of Stardust and DI at the library
http://discovery.larc.nasa.gov/discovery/dpl.html

but I cant find them ohmy.gif
I'm not surprised. Typically, the supporting documentation for AO's isn't fully up-to-date when the AO is released. And based on past experience, I recommend one periodically check (and refresh) the DPL web page throughout the solicitation period as the library is updated based on proposal input, especially after the preproposal conference.

Note that the Discovery Launch Services Information Summary was updated last month.

Posted by: djellison Jan 4 2006, 12:54 AM

The ELV doc is very interesting....I wonder how close that figure they quote for each performance target matches the bill from Boeing or LoMart.

Very interesting chart for DSN charges as well - trying to figure out a rough value - but with 5 contacts a week, 70m DSN access is about $2114 per hour *, with the 34m access being 1/4 of that. It must get to a point where the design of a telecoms system to go onboard a spacecraft is an exercise in accounting more than engineering.

Lots of excellent reading to be had in there - it'll be interesting to see the applications in a few months time.

Doug

(*PS - at say 128kbps, $2114/hr is roughly $37 / megabyte )

Posted by: BruceMoomaw Jan 4 2006, 03:24 AM

About time! Sen. Mikulski managed to gum up this AO for 10 straight months with her personal insistence that the Discovery cost cap must be kept at $350 million. (Jack Dantzler said at the COMPLEX meeting that he is determined to compensate for that delay, and for the fiasco of the last Discovery AO, by picking two Discovery missions this time.)

Posted by: helvick Jan 4 2006, 09:12 AM

QUOTE (djellison @ Jan 4 2006, 01:54 AM)
(*PS - at say 128kbps, $2114/hr is roughly $37 / megabyte )
*

And remember that that effective bitrate drops off following a square law, all other things being equal. So something that supports 4Mbps at Mars drops off to a fairly miserable 2.5kbps at Pluto.

Posted by: ugordan Jan 4 2006, 09:49 AM

QUOTE (helvick @ Jan 4 2006, 10:12 AM)
So something that supports 4Mbps at Mars drops off to a fairly miserable 2.5kbps at Pluto.

It's nitpicking, but I get a figure of 5.9 kbps at Pluto's mean distance from the sun. How'd you get that figure?

Posted by: djellison Jan 4 2006, 10:05 AM

Yup - the maths could get quite interesting. Is it worth spending perhaps $10m upgrading to a slightly heavier version of your ELV to get larger solar arrays so you can have a more powerfull transmitter and thus get more kbps and thus fewer sessions.

Might have had my maths a bit wrong earlier.....but this is all very very 'ballpark guestimation'

say 14 1hr passes of 35m coverage per week ( i.e. the daily uplink for MER plus beep back ) would be something like $2424/hr, or about $34k/week ( $1.7m/year ). The finances for doing MER Relay with Odyssey is probably quite interesting, I think it would probably be something like 1 hr of Odysseys downlink per day is MER related - so a similar figure.



Voyager

QUOTE (Voyager update in the middle of '05)
There were 90.3 hours of DSN scheduled support for Voyager 1 of which 32.6 hours were large aperture coverage
There were 76.5 hours of DSN scheduled support for Voyager 2 of which 25.9 hours were large aperture coverage


Say it's 28 sessions a week, 7 on 70m, 21 on 35m

$6745/hr for the 70m - $400k (as near as makes no difference)
$527k for the 35m - so that week's Voyager DSN ops cost about $927K.

Youch.

Very rough maths - probably very wrong to be honest.

7 x 8hr 70m passes per week, at 5kbps is $377,220 per week, for 984 MBytes - or $552 per floppy disk smile.gif

Doug

Posted by: ugordan Jan 4 2006, 10:23 AM

It just goes to show it's time to switch to optical telecoms. No matter how many watts you pump into your RF transmitter, the vast majority of the transmitted power is simply wasted. The only positive thing a radio comm-link does is loosen the required pointing accuracy, of course due to the same dispersal of the signal.

Posted by: AlexBlackwell Jan 4 2006, 06:49 PM

QUOTE (BruceMoomaw @ Jan 4 2006, 03:24 AM)
About time!  Sen. Mikulski managed to gum up this AO for 10 straight months with her personal insistence that the Discovery cost cap must be kept at $350 million.  (Jack Dantzler said at the COMPLEX meeting that he is determined to compensate for that delay, and for the fiasco of the last Discovery AO, by picking two Discovery missions this time.)
Did Dantzler indicate specifically what he meant by "two Discovery missions"? In the AO, the term "mission" denotes a stand alone Discovery mission, which is distinct from a Discovery Mission of Opportunity (MO).

Posted by: AlexBlackwell Jan 4 2006, 08:51 PM

QUOTE (AlexBlackwell @ Jan 4 2006, 06:49 PM)
Did Dantzler indicate specifically what he meant by "two Discovery missions"?  In the AO, the term "mission" denotes a stand alone Discovery mission, which is distinct from a Discovery Mission of Opportunity (MO).

Section 1.2 of the AO does state: "It is anticipated that approximately three meritorious Discovery Mission investigation proposals will be selected for further study as a result of this evaluation." Note, however, that "further study" refers, I would presume, to the Concept Study phase and not to final selection. On the other other hand, the AO goes on to state that "[o]ne or more MO investigation proposals may also be selected either for study or for immediate implementation."

So, I'm not sure what Danztler's comment means. If he is "determined...[to pick] two Discovery missions this time," does that mean he is committing to final selection of two full Discovery mission investigations (or perhaps one combined with a Discovery MO)? Or is he just re-stating what the AO says (i.e., that three proposals might be downselected for concept study)? If the latter, then that's no big surprise.

Having said that, I wouldn't bet the farm on what is said (or promised) at these COMPLEX-type meetings. Indeed, is Dantzler, even though he is SSD Director and has a tremendous amount of input in the process, the final selecting authority for this AO? I would have thought that Mary Cleave, AA for the Science Mission Directorate, had the final say.

Posted by: mcaplinger Jan 4 2006, 09:46 PM

QUOTE (ugordan @ Jan 4 2006, 02:23 AM)
It just goes to show it's time to switch to optical telecoms. No matter how many watts you pump into your RF transmitter, the vast majority of the transmitted power is simply wasted. The only positive thing a radio comm-link does is loosen the required pointing accuracy, of course due to the same dispersal of the signal.
*


I don't disagree, but...

Optical has the same problem, if you're counting as "wasted" any power that doesn't fall on the receiver's mirror. They're both EM radiation, after all. I'm not sure what the actual efficiency tradeoffs look like, but optical isn't such a slam dunk over RF from a system perspective, because the real engineering-acheivable efficiency gains aren't just the ratio of the wavelengths.

And there's cloudy days, what you do near conjunction, etc.

http://lasers.jpl.nasa.gov/PAGES/about.html has some good background, but obviously optical researchers aren't going to present a completely balanced story.

If you wanted to reduce operations costs for deep-space RF, there would be ways to reduce costs below those of DSN. Some Discovery teams have proposed using USN ( http://www.uspacenetwork.com/index.html ) instead of DSN to save costs.

Posted by: BruceMoomaw Jan 5 2006, 01:17 AM

Dantzler made it clear that if it is at all in his power to do so, he will pick two full-fledged Discovery missions this time around (regardless of whether he adds any MOs as well). In fact, he went on at some length about the fact that Mikulski's move had ticked him off in part because, while he thought he could probably find ONE scientifically worthwhile Discovery mission below the $350 million limit, he thought it very unlikely that he'd be able to find two of them. (He also said that, if budget problems force him to, he'd be willing to stoop to picking that one $350 million mission simultaneously with a more expensive one.)

As for MOs, he hinted that more than one might be picked -- in fact, he said that there may be more than one simultaneous MO picked associated with the Deep Impact extended mission! He made a vague reference to the possibility of "interplanetary observations" for one such Deep Impact MO, along with a comet flyby for another. But I have some trouble seeing what kind of interplanetary observations they could make with DI that would be worth the trouble -- which makes me wonder whether he may really be thinking about flying DI past more than one additional target, CONTOUR-style. Given the need for as big a sampling of different comets and asteroids as we can practically get, it would seem the logical thing to do if it's possible.

Posted by: BruceMoomaw Jan 5 2006, 01:19 AM

Footnote: Mary Cleave does have the final say, at least where New Millennium missions are concerned -- but I must say Dantzler sounded thoroughly confident that he could push this one through.

Posted by: AlexBlackwell Jan 9 2006, 05:39 PM

BTW, for those of you playing along at home, the first set of questions and answers for the AO solicitation has been http://discovery.larc.nasa.gov/PDF_FILES/Q&A-1_11.pdf. Expect many more, especially following the preproposal conference.

Posted by: djellison Jan 11 2006, 07:40 PM

Stardust info up on the library - and DI with a big library here
http://discovery.larc.nasa.gov/discovery/deep_impact_package.html


It would seem they intend to beef up the stardust info after the divert manouver

Doug

Posted by: AlexBlackwell Jan 23 2006, 11:52 PM

The draft agenda for the Febrary 2, 2006, preproposal conferences is now http://discovery.larc.nasa.gov/ppconf.html. Note also that a few documents in the http://discovery.larc.nasa.gov/dpl.html have been updated, as well as the http://discovery.larc.nasa.gov/PDF_FILES/Q&A-3.pdf.

Posted by: AlexBlackwell Jan 24 2006, 05:53 PM

This post is tough to pigeonhole in any one distinct forum/thread, so I'll place it here.

A new report has been released by the National Research Council:

http://www.nap.edu/catalog/11530.html
Committee on Principal-Investigator-Led Missions in the Space Sciences, National Research Council

Posted by: AlexBlackwell Jan 24 2006, 08:52 PM

This is a pretty interesting report, especially Chapter 6.

By the way, for those who are unfamiliar with online books from the National Academies Press (NAP), note that NAP is offering the entire report as a single free downloadable PDF. Just click on the "Download" button under "Free PDFs" and answer truthfully or untruthfully the few questions asked. This will set a cookie on your browser to download the entire 135-page PDF rather than having to skim the report page by page in the "Open Book" online format.

Posted by: BruceMoomaw Jan 24 2006, 10:35 PM

Now, THAT's a useful piece of information, Alex. These things have driven me mad in the past.

Unfortunately, while the last chapter claims to set new guidelines on when a competitively selected mission should or shouldn't get cancelled for breaking its cost cap, it doesn't seem to provide any information that could tell us whether they're recommending the cancellation of "Dawn".

Posted by: BruceMoomaw Jan 25 2006, 12:17 PM

Regarding possible solicitations to the latest Discovery AO: I've been looking for stuff on a possible resubmission of CONTOUR, and have found a piece by Dunham and Farquhar in the May 2004 Annals of the NY Academy of Sciences on the history of trajectory planning for APL's various deep space missions ( http://highorbits.jhuapl.edu/aplmisns.doc ). Be warned that this thing takes forever to download and display -- apparently due to all the drawings in it (plus one reproduction of NEAR's last photo of Eros' surface, with a basketball stuck in it to show how remarkably fine-scale that shot actually was).

At its very end, however, we have a mention of APL's definite plan to submit CONTOUR 2 to the "next Discovery AO" -- which I presume was the abortive one for Discovery 11 -- and a chart of several possible multiple-comet missions for it. All these assume a launch in Oct. 2007, followed by a flyby of Grigg-Skjellerup the following March -- which can't be done now, since the mission if selected this time can't possibly be ready that early. But they then include 2 Earth flybys, with the second in July 2010 -- which COULD be replaced by a direct launch from Earth on that date -- followed by a flyby of Honda-Mrkos-Pajdusakova in August 2011. After that there are several alternative mission continuations that would allow flyby of one more comet, and one that would allow flybys of two more: Finlay in Dec. 2014 and Schwassmann-Wachmann 3 (the fragmented comet that would have been the original CONTOUR's second stop) in Sept. 2022. This last scenario would be followed by another Earth flyby in July 2027 that could presumably be used to set up a fourth comet flyby later, if the craft is still working.

Posted by: AlexBlackwell Jan 25 2006, 05:27 PM

QUOTE (BruceMoomaw @ Jan 25 2006, 12:17 PM)
At its very end, however, we have a mention of APL's definite plan to submit CONTOUR 2 to the "next Discovery AO" -- which I presume was the abortive one for Discovery 11 -- and a chart of several possible multiple-comet missions for it.

If a "CONTOUR-2" is proposed and selected under the Discovery 2006 AO, and if the "http://www.unmannedspaceflight.com/index.php?showtopic=1645&view=findpost&p=38282" somehow materializes, I think a reasonable person might suspect the Discovery Program mission line is simply morphing into an asteroid/comet exploration program.

Posted by: Phil Stooke Jan 25 2006, 05:50 PM

Alex said "I think a reasonable person might suspect the Discovery Program mission line is simply morphing into an asteroid/comet exploration program."

I see what you mean, but we do need to see a good number of these bodies to understand their diversity, and the number of things that can be done under the cost cap is somewhat limited.

Phil

Posted by: JRehling Jan 25 2006, 05:55 PM

QUOTE (BruceMoomaw @ Jan 25 2006, 04:17 AM)
All these assume a launch in Oct. 2007, followed by a flyby of Grigg-Skjellerup the following March -- which can't be done now, since the mission if selected this time can't possibly be ready that early.  But they then include 2 Earth flybys, with the second in July 2010 -- which COULD be replaced by a direct launch from Earth on that date -- followed by a flyby of Honda-Mrkos-Pajdusakova in August 2011.  After that there are several alternative mission continuations that would allow flyby of one more comet, and one that would allow flybys of two more: Finlay in Dec. 2014 and Schwassmann-Wachmann 3 (the fragmented comet that would have been the original CONTOUR's second stop) in Sept. 2022.  This last scenario would be followed by another Earth flyby in July 2027 that could presumably be used to set up a fourth comet flyby later, if the craft is still working.
*


When you say that an Earth flyby could be replaced by a direct launch from Earth, are you relaying a comment in the document? Energy considerations might mean that an Earth flyby accomplishes something that a direct launch could not.

I don't have the desire or the means to impugn the research that went into these mission alternatives, but the complexity of balancing scientific objectives with the very large number of possible comet trajectories makes me want to see a very large effort to generate comet/asteroid mission planning software, to get the most good out of the hardware and mission costs. As a computer scientist, I suspect that even a very good effort might miss some mission plans that are even better. And the ratio of cost/science seems to be better for ground planning than mission operations.

This sounds like a complaint in the absence of facts... it's really just a hunch that more resources for planning might be in order than anyone in the proposal business alone is going to muster before the first funds have been dispersed.

Posted by: AlexBlackwell Jan 25 2006, 06:28 PM

QUOTE (Phil Stooke @ Jan 25 2006, 05:50 PM)
I see what you mean, but we do need to see a good number of these bodies to understand their diversity...

I don't disagree, Phil. However, if this rationale is used to justify the Discovery Program being top-heavy with (or dominated by) asteroid/comet missions, then NASA should at least unequivocally state so. As I'm sure you know, proposers who wish to go after other solar system targets under Discovery expend a lot of resources putting together proposals that, assuming the preceding sentence is true, really don't stand a chance.

QUOTE (Phil Stooke @ Jan 25 2006, 05:50 PM)
...and the number of things that can be done under the cost cap is somewhat limited.

True, asteroid/comet missions are usually relatively cheaper than most, and as many have stated about Discovery's cost caps and future missions, "All the low-hanging fruit has probably been picked."

Posted by: volcanopele Jan 25 2006, 07:27 PM

QUOTE (AlexBlackwell @ Jan 25 2006, 10:27 AM)
If a "CONTOUR-2" is proposed and selected under the Discovery 2006 AO, and if the "http://www.unmannedspaceflight.com/index.php?showtopic=1645&view=findpost&p=38282" somehow materializes, I think a reasonable person might suspect the Discovery Program mission line is simply morphing into an asteroid/comet exploration program.
*

What else is there? Mars has its own low-cost program (though does that include Phobos/Deimos, thinking of Aladdin here...). I guess there were a few Venus ideas last time around (can't seem to remember, VESPER?). Mercury has a mission already on its way. The outer planets are beyond the reach of this program. So that leaves...asteroids and comets. Oh our moon, I forgot about that...

Posted by: AlexBlackwell Jan 25 2006, 07:34 PM

QUOTE (volcanopele @ Jan 25 2006, 07:27 PM)
What else is there?  Mars has its own low-cost program (though does that include Phobos/Deimos, thinking of Aladdin here...).  I guess there were a few Venus ideas last time around (can't seem to remember, VESPER?).  Mercury has a mission already on its way.  The outer planets are beyond the reach of this program.  So that leaves...asteroids and comets.  Oh our moon, I forgot about that...
Aside from Phobos/Deimos, my personal favorite, which falls under Discovery's bailiwick, there are also opportunities for solar-type exploration missions (e.g., Genesis) or astronomical ones like Kepler.

Posted by: BruceMoomaw Jan 25 2006, 10:16 PM

There are at least three Venus Discovery proposals coming up in this round:

(1) VESPER will be resubmitted -- despite the fact that Venus Express should achieve many of its goals. It will be jazzed up by adding the little "VAMP" entry probe that was separately proposed once before. (VAMP's descent camera, which could have provided only very fuzzy high-altitude views, will be replaced by an improved GCMS).

(2) Poor Kevin Baines -- having submitted VESAT five times and struck out repeatedly (sometimes by heartbreakingly close margins) -- has given up on it and will be submitting a cloud-level balloon with a GCMS for protracted atmospheric and cloud studies.

(3) Bruce Campbell will be proposing "VISTA", an orbiter with the kind of subsurface radar sounder that got kicked off Venus Express due to lack of funds (plus a radar altimeter that's higher-resolution than Magellan's, which might allow much better gravity mapping). It may actually be the same "VENSIS" sounder planned for Venus Express -- that is, a clone of MARSIS. He's very skeptical about the ability to age-date Venusian rocks because of their high temperature, and thinks that the stratigraphy which a subsurface radar sounder can provide may be the only way to properly sequence the geological events that actually happened on Venus -- including settling the major question of whether it really did undergo catastrophic resurfacing. He told me at the VEXAG meeting that he simply considers this higher-priority scientifically right now than getting higher-resolution SAR images of Venus, which he could have done if he had instead proposed a Venusian copy of his "Mars Scout Radar" proposal.

I don't think the Discovery program is being deliberately "morphed into a comet/asteroid program" -- but I do think that they are finally running out of really low-cost Solar System missions that can do really good new science (at least until new technologies gradually lower the cost of the missions again), and so small bodies are likely to dominate the program more and more. Certainly, given the need to sample as wide a variety of asteroids, comets and KBOs as possible, missions to visit multiple small-body targets would seem a good, cost-effective choice for the Discovery Program at this point.

In any case, Bush's lunar initiative has now devoured all possible Discovery lunar proposals -- and the Mars Scout program, from its start, included all Phobos/Deimos missions (thus infuriating Jeffrey Bell, who admittedly infuriates easily). As for extrasolar-planet astronomy satellites, keep in mind that Kepler's cost has mushroomed to over $500 million -- with NASA's new Universe Division neverthless continuing to support it on the grounds that it's now an integral part of the extrasolar-planet search program (which, as Andy Dantzler said, means that "I don't have to worry about the thing anymore.") If later extrasolar-planet Discovery proposals are likely to undergo comparable cost overruns, this of course reduces their chances of being picked. It will be interesting to see whether they get enough science out of the damaged Genesis samples to rule out any thoughts of a reflight -- especially since oxygen and nitrogen measurements were both its highest scientific priorities and the ones most seriously contaminated by the crash.

But those last two categories raise the question of whether it might be better for NASA to combine ALL its competitively-picked space science missions within the same cost band into a unified competition, regardless of whether they happen to be Solar System, astronomy, or Sun-Earth Connection studies. (I've already mentioned that the possibility has been raised of incorporating Solar Probe into the New Frontiers program, since it's in the same price range.) This would seem to be more scientifically cost-effective overall.

Posted by: BruceMoomaw Jan 25 2006, 10:24 PM

Answering John Rehling's question: no, there's no specific reference in the Dunham piece to a direct 2010 launch from Earth being capable of sending CONTOUR 2 to Comet "HMP" (I flatly refuse to respell its name again) in 2011. But the flyby would be only 0.08 AU from Earth and only 0.04 AU closer to the Sun than Earth is, so I presume it could easily be done by direct launch with a small booster.

Posted by: AlexBlackwell Jan 25 2006, 11:42 PM

QUOTE (BruceMoomaw @ Jan 25 2006, 10:16 PM)
...and the Mars Scout program, from its start, included all Phobos/Deimos missions...

My understanding is that exploration of Phobos and Deimos is not covered under the Mars Exploration Program (MEP), which also constrains and guides the science objectives of Mars Scout mission investigations -- at least that was the case under the http://research.hq.nasa.gov/code_s/nra/current/AO-02-OSS-02/index.html.

Posted by: BruceMoomaw Jan 26 2006, 01:49 AM

Faith Vilas, Discovery Program Scientist at the July 2002 "Discovery Program Lessons Learned Workshop" ( http://discovery.larc.nasa.gov/PDF_FILES/DiscoMinutes3.pdf , pg. 5):

"Q: Are there any major changes from the last AO [for the next one in 2003]?

"A: Mars, Phobos, and Deimos will now be in Mars Scout -- so they are no longer in
Discovery."

I've seen no indication that they have changed this back since. Jeff Bell -- who was associated with the "Gulliver" Deimos sampling mission -- has been bitching about it to me for some time. I will agree with him and you that it doesn't make any sense; but then, that fact means that it fits in very well with the US space program in general.

Posted by: AlexBlackwell Jan 26 2006, 01:59 AM

QUOTE (BruceMoomaw @ Jan 26 2006, 01:49 AM)
Faith Vilas, Discovery Program Scientist at the July 2002 "Discovery Program Lessons Learned Workshop" ( http://discovery.larc.nasa.gov/PDF_FILES/DiscoMinutes3.pdf , pg. 5):

"Q: Are there any major changes from the last AO [for the next one in 2003]?

"A: Mars, Phobos, and Deimos will now be in Mars Scout -- so they are no longer in
Discovery."

I've seen no indication that they have changed this back since.  Jeff Bell -- who was associated with the "Gulliver" Deimos sampling mission -- has been bitching about it to me for some time.  I will agree with him and you that it doesn't make any sense; but then, that fact means that it fits in very well with the US space program in general.

Thanks. I must have missed the change, but now that I read those minutes, I do vaguely recall it. I do know that Dan Britt et al. originally envisioned Gulliver as a Discovery Program mission.

Posted by: djellison Jan 26 2006, 10:32 AM

If you think about it - for Discovery money, you cant' really do anything Jovian or beyond.

Mars is out, Mercury's done and it's unlikely you'd get a nod for another Mercury mission the next decade or so ( at least until Messenger has lived out its primary mission ) - and VEX is likely to teach us what else we might like to learn about Venus, but not for 5 years or so. Then you have Lunar missions - with LRO basically stealing that scene for the next few years.

So you're left with Earth orbital and L1/L2 type missions (Genesis, Kepler), or Comets and Asteroids.

Doug

Posted by: tedstryk Jan 26 2006, 01:48 PM

Well, for Venus, an atmospheric probe might be possible. I wonder about a Mercury hard lander. Also, a Jovian entry probe mission has been mulled in the past, but it has always died based on the fact that the science that could be done on a discovery budget may not justify the cost of getting there.

Posted by: Phil Stooke Jan 26 2006, 05:58 PM

Venus is relatively easy to land on, compared with Mars at any rate. I would like to see quite a few more landings, targeted for specific geologic units. I think they could be done as Discovery missions. But we've covered this ground before!

Phil

Posted by: AlexBlackwell Jan 26 2006, 07:22 PM

QUOTE (BruceMoomaw @ Jan 26 2006, 01:49 AM)
Jeff Bell -- who was associated with the "Gulliver" Deimos sampling mission -- has been bitching about it to me for some time.  I will agree with him and you that it doesn't make any sense...
It does make perfect sense, however, if NASA has no intention of flying a dedicated Phobos/Deimos mission. Moving "jurisdiction" for any such mission to the Mars Scout line, for all intents and purposes, is a death knell since Mars Scout proposals must be responsive to MEP scientific goals. Neither Phobos nor Deimos rate high (if at all) under MEP. At least in the Discovery Program, missions like Aladdin and Gulliver had a chance, so, in this rare instance, I'll have to agree with your example of Bell's "bitching."

Posted by: AlexBlackwell Jan 26 2006, 07:26 PM

QUOTE (tedstryk @ Jan 26 2006, 01:48 PM)
Well, for Venus, an atmospheric probe might be possible.  I wonder about a Mercury hard lander.  Also, a Jovian entry probe mission has been mulled in the past, but it has always died based on the fact that the science that could be done on a discovery budget may not justify the cost of getting there.

Your examples show that there are many possibilities for non-cometary, non-asteroidal missions under Discovery, though a more significant cost cap increase would make alternatives more realistic.

Posted by: odave Jan 26 2006, 07:37 PM

How about a solar mission - or has Sol's "low hanging fruit" already been picked?

Posted by: tty Jan 26 2006, 11:30 PM

QUOTE (AlexBlackwell @ Jan 26 2006, 09:22 PM)
It does make perfect sense, however, if NASA has no intention of flying a dedicated Phobos/Deimos mission.  Moving "jurisdiction" for any such mission to the Mars Scout line, for all intents and purposes, is a death knell since Mars Scout proposals must be responsive to MEP scientific goals.  Neither Phobos nor Deimos rate high (if at all) under MEP.  At least in the Discovery Program, missions like Aladdin and Gulliver had a chance, so, in this rare instance, I'll have to agree with your example of Bell's "bitching."
*


It seems to me that the fastest and simplest way to obtain a varied sample of Martian material would be on Phobos. Rocks from every major impact on Mars must have ended up there and You don't have to go nearly as deep into the gravity well as for the surface of Mars.
Perhaps a mission for a future improved Haybusa?

tty

Posted by: BruceMoomaw Jan 26 2006, 11:33 PM

Where solar studies are concerned, with one exception competed ones are suppposed to fall under the Explorer bailiwick rather than Discovery. The exception, of course, was Genesis, presumably because its main purpose was to do a really detailed isotopic analysis of the Sun's composition to provide additional insight on the formation processes of the planets. By itself, though, Genesis shows how fuzzy the borderlines between different basic branches of space science can be -- and again suggests the possibility that maybe NASA ought to lump ALL its competed missions within a single cost range together in one AO, rather than competing Discovery and Explorer (or New Frontiers and larger Explorers) separately. (The fact that small extrasolar-planet astronomy satellites are also put in the Discovery program rather than Explorer again shows the arbitrariness of this.)

Posted by: AlexBlackwell Jan 26 2006, 11:36 PM

QUOTE (tty @ Jan 26 2006, 11:30 PM)
It seems to me that the fastest and simplest way to obtain a varied sample of Martian material would be on Phobos. Rocks from every major impact on Mars must have ended up there and You don't have to go nearly as deep into the gravity well as for the surface of Mars.
Perhaps a mission for a future improved Haybusa?

Actually, perhaps a better case can be made for Deimos, as Britt et al. do with the Gulliver Deimos Sample Return mission concept (e.g., http://www.lpi.usra.edu/meetings/metsoc2005/pdf/5274.pdf, http://www.cosis.net/abstracts/COSPAR04/03897/COSPAR04-A-03897.pdf, http://www.aas.org/publications/baas/v35n4/dps2003/212.htm).

Posted by: BruceMoomaw Jan 26 2006, 11:44 PM

As for Ted Stryk's suggestions: Venus entry probes are indeed plausible as Discovery missions, and in fact have been proposed from the very start of the program. So have Venus balloons: consider Ron Greeley's VEVA, which involved not just a balloon but one that would drop four little camera-equipped impactors as it blew over different parts of the planet.

But I imagine a Mercury hard lander, which would require a really major propulsion system, would probably be sufficiently costly that it would have to fall into the New Frontiers category (where it is one of the ideas being given serious consideration).

The same seems to be true of even a single Jovian entry probe (where presumably the goal would be to penetrate a lot deeper than the Galileo probe did, as well as coming down in a more representative part of the planet's atmosphere). However, one recent paradigm shift seems to be toward the idea that you don't really need deep entry probes to provide good compositional information on the other three giant planets -- and so the idea is now being strongly pushed that the next giant-planet entry probe mission should be a New Frontiers-class Saturn flyby that would just drop off two or three vented Galileo-type entry probes (or maybe even just one), with the flyby craft also observing the greater depths of Saturn's atmosphere with a Juno-type microwave spectrometer. This of course could also be done for Uranus or Neptune if we decided to do so before flying the much more complex Neptune Orbiter mission, although in that case you'd want to add a considerable number of other instruments to the flyby craft to make additional observations of the planet and its moons.

A Saturn Multiprobe Flyby, moreover, might be able to use solar power rather than an RTG -- just such a suggestion was made years ago, using a modified "INSIDE Jupiter" craft as the Saturn probe carrier, with no orbital insertion motor but a second pair of big solar arrays added.

Posted by: JRehling Jan 27 2006, 01:37 AM

Other options would include smash-and-grab sample returns for airless bodies, with Mercury and Europa being the primary candidates of interest. Incidentally, an idea I don't recall seeing elsewhere would be a Stardust type mission with Saturn's *rings* as the object. (Jupiter's rings also an option.) Sampling the plumes of Io or Enceladus would also be possible, although if primitive species dominate, that would be a waste of money vs. a GCMS fly-through (which has been done, in both cases).

Posted by: AlexBlackwell Feb 6 2006, 08:58 PM

A new document (http://discovery.larc.nasa.gov/PDF_FILES/Stardust_End-of-Mission_State.pdf) was added to the http://discovery.larc.nasa.gov/dpl.html today.

Posted by: AlexBlackwell Feb 7 2006, 08:55 PM

Presentations listed in the agenda for the Pre-Proposal Conference (February 2, 2006) are now http://discovery.larc.nasa.gov/ppconf.html.

Posted by: AlexBlackwell Feb 7 2006, 11:07 PM

Presentations from the Lessons Learned Workshop (February 2, 2006) are also now http://discovery.larc.nasa.gov/LLWorkshop2006.html.

Posted by: AlexBlackwell Feb 9 2006, 12:00 AM

The AO has been amended. Click http://nspires.nasaprs.com/external/solicitations/summary.do?method=init&solId={AAF26E94-4B3C-6544-9EB2-A3E31E507790}&path=open for more details.

Posted by: AlexBlackwell Feb 13 2006, 08:01 PM

The Q&A's have been http://discovery.larc.nasa.gov/PDF_FILES/Q&A-4.pdf.

Posted by: bmnky Feb 21 2006, 06:15 PM

QUOTE (BruceMoomaw @ Jan 25 2006, 10:16 PM) *
(2) Poor Kevin Baines -- having submitted VESAT five times and struck out repeatedly (sometimes by heartbreakingly close margins) -- has given up on it and will be submitting a cloud-level balloon with a GCMS for protracted atmospheric and cloud studies.


Does anybody know the name of Baines' new proposal?

Posted by: helvick Feb 21 2006, 07:03 PM

QUOTE (AlexBlackwell @ Feb 13 2006, 08:01 PM) *
The Q&A's have been http://discovery.larc.nasa.gov/PDF_FILES/Q&A-4.pdf.

Nice (for us at least) to see this re-iterated.
QUOTE
By default, all NASA science data from Discovery missions is public immediately. However, a short period for exclusive rights to data may be proposed with justification. The proposed period of exclusivity should be the shortest period that is consistent with optimizing the science return from the mission and, except under exceptional circumstances, may not exceed six months…

If only such a policy applied to engineering data.

Posted by: djellison Feb 21 2006, 07:10 PM

Helvick, you should have a look at MER mobility reports smile.gif

Doug

Posted by: helvick Feb 21 2006, 08:17 PM

QUOTE (djellison @ Feb 21 2006, 07:10 PM) *
Helvick, you should have a look at MER mobility reports smile.gif

Doug

Yea I know - I still haven't found much of what I'd like to see (power system data, anything to give an idea of performance and wear and tear over time) but I haven't looked hard enough yet so I suppose I should stop complaining until I've done that. smile.gif

Posted by: djellison Feb 21 2006, 08:41 PM

Remember - much of that is probably hidden by ITAR issues.

Doug

Posted by: helvick Feb 21 2006, 09:21 PM

QUOTE (djellison @ Feb 21 2006, 08:41 PM) *
Remember - much of that is probably hidden by ITAR issues.


Yep I know that too. A rather obstructive piece of legislation from my point of view but what can you do, dems the rules as they say.

Posted by: AlexBlackwell Feb 21 2006, 10:58 PM

QUOTE (AlexBlackwell @ Feb 7 2006, 11:07 PM) *
Presentations from the Lessons Learned Workshop (February 2, 2006) are also now http://discovery.larc.nasa.gov/LLWorkshop2006.html.

There's a new addition (added today) to the "Lessons Learned" page: "http://discovery.larc.nasa.gov/PDF_FILES/TMC_Paper_21Feb06.pdf."

Posted by: AlexBlackwell Feb 23 2006, 05:59 PM

New Q&A's have been http://discovery.larc.nasa.gov/PDF_FILES/Q&A-6b_1.pdf.

Posted by: AlexBlackwell Feb 28 2006, 06:17 PM

A second amendment to the AO has been http://nspires.nasaprs.com/external/solicitations/solicitationAmmendments.do?method=init&solId={AAF26E94-4B3C-6544-9EB2-A3E31E507790}&path=open.

Posted by: AlexBlackwell Mar 15 2006, 11:44 PM

The Q&A's have been http://discovery.larc.nasa.gov/PDF_FILES/Q&A-10.pdf.

Posted by: AlexBlackwell Mar 23 2006, 10:31 PM

A http://discovery.larc.nasa.gov/XLS_FILES/Discovery12PPCAttendeeslist.xls to the February 2, 2006, pre-proposal conference is now available.

Posted by: BruceMoomaw Mar 23 2006, 10:50 PM

Some rather big names missing from that list. No Kevin Baines or Tom Campbell (both of whom have already announced that they intend to propose Venus missions); no Derek Sears (of HERA); no Veverka proposing a repeat of CONTOUR. Other members of their teams may have attended instead, of course.

Posted by: AlexBlackwell Sep 8 2006, 01:13 AM

Of course, close observers will note that by now it is "http://discovery.larc.nasa.gov/schedule.html" for the AO selections, assuming there are any, to be announced. biggrin.gif

Posted by: Mariner9 Sep 8 2006, 06:54 PM

I must be a close observer, because I've been wondering when in September the announcement (if any) will arrive.

Normally I don't really have any guesses as to what kind of missions we will see in the finalists, but I can't help wondering this time if we will see a Venus probe of some kind.

Lunar, Mars, and now even Mars moons, are off limits. We've done several comet missions, and two asteroid missions, and the only Jupiter proposals ever made under discovery were all wrapped up into the Juno New Fronteirs mission. The Messenger mission nearly broke the bank, but it is now safely on it's way to Mercury.

While asteroids and comets still have lots of targets still out there, I'd bet good money on at least one of the comet flyby "Missions of Opportunity" to be selected, so it just seems like it might finally be Venus' turn.

Posted by: AlexBlackwell Sep 8 2006, 09:03 PM

Yeah, these downselects are notoriously unpredictable, which, I guess, is a good thing from a fairness standpoint. Now whether the selections will make any sense is another matter tongue.gif

I, too, think some sort of Venus proposal could make the cut. However, I wouldn't be surprised if a cometary/asteroid mission(s) is/are selected, especially given Stardust's success, the CONTOUR failure, the partial failure of Hayabusa, and the descope, near-death of Dawn.

Having said that, nothing would surprise me at this point, except, of course, another round of non-selections, as happened with the previous Discovery AO.

Posted by: mcaplinger Sep 8 2006, 09:46 PM

QUOTE (Mariner9 @ Sep 8 2006, 11:54 AM) *
Lunar, Mars, and now even Mars moons, are off limits.

Lunar missions weren't off-limits as far as I can tell from the AO. At least, we proposed one.

Posted by: AlexBlackwell Sep 8 2006, 09:56 PM

QUOTE (mcaplinger @ Sep 8 2006, 11:46 AM) *
Lunar missions weren't off-limits as far as I can tell from the AO. At least, we proposed one.

My understanding of this AO, too, is that it only excludes Mars.

Posted by: JRehling Sep 13 2006, 01:41 AM

QUOTE (AlexBlackwell @ Sep 8 2006, 02:03 PM) *
I, too, think some sort of Venus proposal could make the cut.


I think there's a kind of "knapsack problem" going on with Venus exploration. There's a will (or so we infer) to move ahead, but since missions must be shoehorned into Discovery/NF size caps, it may be inconvenient to design a series of missions each at just the right size and still go forward sensibly exploring the place.

One simple experiment that must be flown is a top-notch mass spectrometer to nail down the minor atmospheric constituents. The cloud composition is still partially a mystery (two mysteries: is there chlorine, and what is the UV-dark stuff). Some descent imaging to test the feasability of aerobot-height multispectral visual surveys would be a logical precedent to a later, bigger mission. And surface studies galore remain.

When you take the ESA orbiter, the possible ISAS orbiter yet to come, and the vaguely-scoped NF mission to come, it's not clear if any kind of mission we've ever seen proposed before would squeeze neatly into the gap between the already pencilled-in missions. Whereas the close-finishers Discovery missions to Venus that have come before have all been orbiters, an entry probe could be the possible winner now. That only means that the mission has to stand up to competition that may return science for weeks or months while such a Venus mission would only return data for hours. Of course, Deep Impact didn't last much longer than that -- but it had a little more glory to it than a simple entry probe.

I'd love to see an entry probe that performs 15 good minutes of surface science after landing. That would be a great mission.

The instrument failure on VEx opens a small window for another Venus orbiter to recover that science, but that doesn't sound like a tremendous concept by itself.

Posted by: gpurcell Sep 13 2006, 04:04 PM

I wonder if something they might try to do is pick a mission with a fairly rapid science turnaround. That would (to an extent) make up for the massive delay in this latest round. A quick simple mission to Venus or the Moon might be just the trick!

Posted by: Mariner9 Sep 13 2006, 06:15 PM

I always suspected that one of the appeals to Deep Impact was the fairly rapid mission. Countour (had it suceeded) also performed it's first comet encounter after only about a year if I recall correctly.

One of the original goals of Discovery was to reduce mission lifecycle from 10-15 years down to well under 10. This made the politicians who funded it feel like something would be accomplished not only during their lifetime, but maybe even while still in office. At the same time, you get more frequent missions, and the public might stay interested.

But if you make all of your missions fly as long as StarDust (7 years) or Messenger (originally 5, now 7 years) the payoff is pushed out to a rather distant future. Add in the time required for the proposal, study, downselect, and development times, those missions were definately going over the 10 year mark.

I tend to agree with you, one of the appeals to a Venus or Lunar mission is the quick flight time.

Even so, with LRO and the whole Lunar Robotic program, I hope Discover and New Fronteirs skips the moon (no matter the scientific value) and go for more distant and less frequently visited targets.

Posted by: Bart Oct 6 2006, 12:35 AM

Any news on the selections? I make it now Proposal Receipt + 6 Months and I haven't heard a peep.

Bart

Posted by: AlexBlackwell Oct 11 2006, 06:48 PM

From Brad Thomson, http://www.planetary.org/blog/article/00000726/ for Emily, about NASA Night at DPS:

QUOTE
Colleen [Hartmann] also dispelled a rumor that an announcement in the Discovery Program would be forthcoming this evening. Discovery Missions are lower cost missions that are competitively selected every few years. There are some 20 missions competing for a single slot, so competition is fierce.

That's not really much news but Thomson noted that Hartmann said "Mars Scout selection will occur in before the year is out."

Posted by: NASA Geek Oct 30 2006, 11:37 PM

NASA has announced selections for the Discovery 2006 AO. The press release is posted on SpaceRef:
http://www.spaceref.com/news/viewpr.html?pid=21149

Posted by: Mariner9 Oct 30 2006, 11:44 PM

Seven months and counting.... and the Discovery mission canidates are finally chosen.

http://www.nasa.gov/home/hqnews/2006/oct/HQ_06342_Discovery_AO.html


"NASA Monday selected concept studies for missions that would return a sample of an enigmatic asteroid, probe the chemistry of Venus' atmosphere and reveal the interior structure and history of the Earth's moon.

Also selected for further study are three missions of opportunity that would make new use of two NASA spacecraft that have completed their primary objectives."


Much to my surprise, VESPER has reappeared and made it into the Concept study phase. I figured that after being studied so many times that it was cursed to never get selected, but maybe it is something like "Inside Jupiter", which kept popping up in different proposals until it finally gained approval as the JUNO mission under New Frontiers.

The moon mission seems somewhat lacking in scope.... a dedicated gravity mapping mission. I'm sure you can learn a lot doing that, but it also seems like it could be a rather limited payload, and cheap mission. I find myself wondering if the reason it made the cut is to have a fallback mission if the other two come back as too expensive or infeasable for some reason.

Posted by: nprev Oct 31 2006, 01:04 AM

I like the new missions for Deep Impact and Stardust, though.

This "EPOCh" mission for DI sounds intriguing:

"The Extrasolar Planet Observations and Characterization (EPOCh) mission would use the high-resolution camera on the Deep Impact spacecraft to search for the first Earth-sized planets detected around other stars. L. Drake Deming of Goddard is EPOCh's principal investigator."

blink.gif ...what does DI have that Hubble doesn't? Are we just talking availability here, or does DI's HRC have better resolution for such a task?

Posted by: Stephen Oct 31 2006, 01:10 AM

QUOTE (Mariner9 @ Oct 31 2006, 10:44 AM) *
Seven months and counting.... and the Discovery mission canidates are finally chosen.

http://www.nasa.gov/home/hqnews/2006/oct/HQ_06342_Discovery_AO.html

"missions of opportunity": that's a term of phrase NASA may now want to think more carefully about using for these missives; it kind of sounds like they're talking about the ongoing adventures of a certain Mars rover biggrin.gif
======
Stephen

Posted by: Jim from NSF.com Oct 31 2006, 02:32 AM

QUOTE (Stephen @ Oct 30 2006, 08:10 PM) *
"missions of opportunity": that's a term of phrase NASA may now want to think more carefully about using for these missives; it kind of sounds like they're talking about the ongoing adventures of a certain Mars rover biggrin.gif
======
Stephen


Only a small audience would think of it that way. I worked MER and didn't think of it that way. They were never Spirit and Opportunity, they are MER A & B to me.

targets of ....., missions of ......, payloads of......, the term is used in many more ways than referring one rover

Posted by: nprev Oct 31 2006, 05:34 AM

huh.gif Jim, I didn't understand your comment.

Posted by: edstrick Oct 31 2006, 09:29 AM

"...would return a sample of an enigmatic asteroid,..."

The <derogatory-scatalogical-term-deleted>-wits in the PR office were too stupid to indicate what asteroid or (equally important) what KIND of asteroid in the press release.

morons.

Posted by: mchan Oct 31 2006, 12:08 PM

It's an E-type asteroid. rolleyes.gif

Posted by: Phil Stooke Oct 31 2006, 04:08 PM

nprev:

"This "EPOCh" mission for DI sounds intriguing:

"The Extrasolar Planet Observations and Characterization (EPOCh) mission would use the high-resolution camera on the Deep Impact spacecraft to search for the first Earth-sized planets detected around other stars. L. Drake Deming of Goddard is EPOCh's principal investigator."

...what does DI have that Hubble doesn't? Are we just talking availability here, or does DI's HRC have better resolution for such a task?"

----------

I know nothing about EPOCH and was very surprised to see it here. The only thing Deep Impact can have that Hubble doesn't is time. It could stare at a transiting exoplanet for long periods, monitoring multiple eclipses - well, not stare presumably, but take lots of pics, or maybe do a deliberately blurred and offset image like Galileo with Comet SL9 - whereas Hubble time is far too valuable to deploy like that.

Phil

Posted by: gpurcell Oct 31 2006, 06:41 PM

Given the missions selected, I think the odds are HEAVILY slanted towards the next Discovery selection being VESPER.

Posted by: gpurcell Oct 31 2006, 06:44 PM

QUOTE (Mariner9 @ Oct 30 2006, 11:44 PM) *
Seven months and counting.... and the Discovery mission canidates are finally chosen.

http://www.nasa.gov/home/hqnews/2006/oct/HQ_06342_Discovery_AO.html
The moon mission seems somewhat lacking in scope.... a dedicated gravity mapping mission. I'm sure you can learn a lot doing that, but it also seems like it could be a rather limited payload, and cheap mission. I find myself wondering if the reason it made the cut is to have a fallback mission if the other two come back as too expensive or infeasable for some reason.


I agree. It may also preserve ability to do Moon science needed for VSE if the robotic portion of that program gets axed.

Posted by: tty Oct 31 2006, 06:56 PM

"Origins Spectral Interpretation, Resource Identification and Security (OSIRIS)"

That must be some kind of a record for a contrived acronym. blink.gif

tty

Posted by: Paolo Oct 31 2006, 07:18 PM

QUOTE (nprev @ Oct 31 2006, 02:04 AM) *
I like the new missions for Deep Impact and Stardust, though.

This "EPOCh" mission for DI sounds intriguing:

"The Extrasolar Planet Observations and Characterization (EPOCh) mission would use the high-resolution camera on the Deep Impact spacecraft to search for the first Earth-sized planets detected around other stars. L. Drake Deming of Goddard is EPOCh's principal investigator."

blink.gif ...what does DI have that Hubble doesn't? Are we just talking availability here, or does DI's HRC have better resolution for such a task?


I think it would be something like this proposal http://www.stelab.nagoya-u.ac.jp/hawaii/hawaii_DIME_jan2004w.ppt
Speaking of the new Stardust mission, this somewhat reinforces my belief that Deep Impact was a sort of job unfinished

Posted by: Paolo Oct 31 2006, 07:33 PM

QUOTE (gpurcell @ Oct 31 2006, 07:41 PM) *
Given the missions selected, I think the odds are HEAVILY slanted towards the next Discovery selection being VESPER.


IIRC VESPER was not too different from Venus Express when it was proposed a few years ago.

Posted by: Mariner9 Oct 31 2006, 11:36 PM

QUOTE (edstrick @ Oct 31 2006, 01:29 AM) *
"...would return a sample of an enigmatic asteroid,..."

The halfwits in the PR office were too stupid to indicate what asteroid



How about Asteroid 624 Victor?


I found a scientific paper called:
Trojan Asteroid 624 Hektor: Evolution of an Enigma
by W.K. Hartmann.

http://adsabs.harvard.edu/abs/1980BAAS...12Q.837H

The great thing about the internet, there is hardly a question that can't be answered (with tongue firmly planted in cheek) using Google.

Posted by: OWW Nov 1 2006, 12:14 AM

I don't understand why Deep Impact is considered for an extended mission when its High Res imager is Badly Blurred Beyond Belief. I remember a lot of talk about deconvolution, but a year later all I see on their website are these pictures:

http://deepimpact.jpl.nasa.gov/gallery/jpg/doy185_Jul4_HRI_Impact1.jpg
http://deepimpact.jpl.nasa.gov/gallery/jpg/goneinaflash.jpg
http://deepimpact.jpl.nasa.gov/gallery/jpg/nucleus-516.jpg

What's the point of flying this camera to another comet? huh.gif

Posted by: Mariner9 Nov 1 2006, 12:37 AM

There are a lot better pics out there than the ones you picked.

http://deepimpact.jpl.nasa.gov/gallery/jpg/HRI_937_1.jpg

As I understand it, the idea is that we have only seen 4 comets close up, and each one looked very different from the last.
As I recall, the best resolution on Deep Impact images were around 10 meters per pixel. Compare that to around 100 m at Halleys back in 1986, and over 30 m at Borelley (Deep Space 1), and you can appreciate the improvement.

The Contour Discovery mission was funded at around 150 million to get a look at only 2 comets (maybe 3 if lucky, which it most definately was not). So NASA was willing to spend about 75 million dollars per comet on that mission. 30 million for the Deep Impact extended mission seems like a good bargain in comparision.

Posted by: nprev Nov 1 2006, 01:41 AM

QUOTE (Paolo @ Oct 31 2006, 11:18 AM) *
I think it would be something like this proposal http://www.stelab.nagoya-u.ac.jp/hawaii/hawaii_DIME_jan2004w.ppt

Okay, I think I get it now...long-parallax baseline imaging of nearby stars looking for Earth-sized object transits? Sounds interesting, but I have to wonder just how many extrasolar systems would happen to have ecliptic planes along our LOS for a given observation... huh.gif

Posted by: djellison Nov 1 2006, 07:41 AM

QUOTE (OWW @ Nov 1 2006, 12:14 AM) *
What's the point of flying this camera to another comet? huh.gif


Because it's still the best camera for looking at Comets during a flyby we've ever had, and combined with its ability to take IR Spectra, it offers a very very cheap way of exploring another comet for something less than 10th the price of a new dedicated mission.

And - when it comes to measuring transits with an out of focus camera....all you're doing is counting photons, and that can be done just as well with an out of focus instrument in actual fact...it's not ideal, but it will do the job (and if it couldn't, they wouldn't have been selected for the next study phase)

Doug

Posted by: ugordan Nov 1 2006, 09:47 AM

QUOTE (djellison @ Nov 1 2006, 08:41 AM) *
all you're doing is counting photons, and that can be done just as well with an out of focus instrument in actual fact...it's not ideal, but it will do the job

It may in fact be ideal because you don't want sharp images of the stars as the physical structure of the CCD pixels has discontinuities. If you had a very sharp, point-like star image, small attitude disturbances will project the image on different parts of the pixel region, possibly on the boundary between two pixels. This would make the brightness appear to oscillate. With an out-of-focus image, you sum up the smudged area which is less prone to such artifacts. A similar think is done in star scanners, AFAIK.

Posted by: djellison Nov 1 2006, 10:03 AM

Yup - we had that discussion a while back about star scanners being out of focus to produce a little ring of the star which is easier to identify with software than a sharp star and cosmic ray hits etc.

Posted by: monitorlizard Nov 1 2006, 11:23 AM

Concerning the Discovery program selection this round, I remember (but can't find) an article where the head of Discovery said that, because there was no mission selected in the previous Announcement of Opportunity, the program had extra money and he would fight hard for two missions to be selected this time. However, it might be more realistic to expect one new mission and the Stardust and Deep Impact extensions to be funded.

All of this is dependent on the NASA manned program not raiding Discovery's extra funds, of course.

Posted by: Mariner9 Nov 1 2006, 02:58 PM

I remember that also. I'm fairly sure that was Andy Dantzler who said it, and he is now gone. It would be nice to see two Discovery missions selected (considering the 5 year gap since the last selection) but I'm not holding my breath.

Given the events of the last couple years, I just hope we still get the New Frontiers #3 AO in 2008. That program started out as an "every 3-4 years" and turned into "every 5 years" by the second mission. This does not bode well.

Posted by: ugordan Nov 1 2006, 04:15 PM

QUOTE (djellison @ Nov 1 2006, 11:03 AM) *
we had that discussion a while back about star scanners being out of focus to produce a little ring of the star which is easier to identify

Actually, I was the one who http://www.unmannedspaceflight.com/index.php?s=&showtopic=3394&view=findpost&p=73477 that in both cases so it should be taken with a grain of salt. smile.gif I do, however, seem fairly certain I read that somewhere -- most likely a writeup on Cassini.

Posted by: Floyd Nov 1 2006, 06:19 PM

There are some Cassini sky shots from Sept 30, 2006 where they seem to do long exposures with camera drift. It makes the real star track very different from the cosmic rays. http://saturn.jpl.nasa.gov/multimedia/images/raw/raw-images-details.cfm?feiImageID=85342

I assume the streaked star images were intentional??

Floyd

Posted by: JRehling Nov 1 2006, 10:53 PM

QUOTE (edstrick @ Oct 31 2006, 01:29 AM) *
"...would return a sample of an enigmatic asteroid,..."

The <derogatory-scatalogical-term-deleted>-wits in the PR office were too stupid to indicate what asteroid or (equally important) what KIND of asteroid in the press release.


That's just how enigmatic it is.

Posted by: Comga Nov 2 2006, 04:31 AM

QUOTE (ugordan @ Nov 1 2006, 10:15 AM) *
Actually, I was the one who http://www.unmannedspaceflight.com/index.php?s=&showtopic=3394&view=findpost&p=73477 that in both cases so it should be taken with a grain of salt. smile.gif I do, however, seem fairly certain I read that somewhere -- most likely a writeup on Cassini.


Yes, indeed, star trackers and star cameras do blur the images of the stars. As you said, this does enable the system to find the "centroid" or center-of-gravity so to speak of the spot, to a small fraction of the pixel dimension.

Defocus is one way to do this blurring, and is definitely used on commercial products. Others have (and may still) use a camera that just doesn't form a good image, although the blur still has to be round (to a first approximation). Using focus requires very stable systems, so that the blur spot doesn't grow or shrink too much.

There are papers in the professional literature (AIAA proceedings for instance) on the software that determines orientation in space from an image of stars. Extremely clever programing, although some are even more clever than others.

Posted by: Phil Stooke Nov 2 2006, 05:51 PM

For the comment by Dantzler about funding two missions if possible, check out post # 13 in this thread (page 1). The information came from Bruce Moomaw.

Phil

Posted by: Comga Nov 3 2006, 04:42 AM

QUOTE (BruceMoomaw @ Jan 4 2006, 07:17 PM) *
As for MOs, he (Dantzler) hinted that more than one might be picked -- in fact, he said that there may be more than one simultaneous MO picked associated with the Deep Impact extended mission! He made a vague reference to the possibility of "interplanetary observations" for one such Deep Impact MO, along with a comet flyby for another. But I have some trouble seeing what kind of interplanetary observations they could make with DI that would be worth the trouble -- ..

Well, now you know: EPOCh ! Exosolar Planet Observation & Characterization. Using the defocused 30cm telescope as a photometer and spectrophotometer for transits of very large exoplanets.

and from nprev and Phil Stooke:

..what does DI have that Hubble doesn't? Are we just talking availability here, or does DI's HRC have better resolution for such a task?"

The only thing Deep Impact can have that Hubble doesn't is time. It could stare at a transiting exoplanet for long periods, monitoring multiple eclipses - well, not stare presumably, but take lots of pics, or maybe do a deliberately blurred and offset image like Galileo with Comet SL9 - whereas Hubble time is far too valuable to deploy like that.
Phil

Generally correct. It can take long sequences of small images taken rapidly. In addition, the blur, while not originally intentional, would be a benfit here. It will spread the star light out so that the detector can use much longer exposures with much improved radiometry (Can Hubble be defocused significantly and was this done when they observed transits by HD 149026b?) The amount of blurring can be more important than the aperture for these measurements of bright stars. Plus Deep Impact was designed to take small images rapidly, which could be used to determine the time profile of the transits, which is important for determining size. It also has an imaging spectrometer that goes out to 4.8 microns.

Not only is Hubble's time too valuable to stare for days or weeks, but it gets interrupted by orbiting so close to the Earth, which blocks much of the sky for up to half of each orbit.

Note that DIXI (Deep Impact eXtended Investigation of comets), EPOCh, and the Stardust extended mission actually won only $250K for further studies. This surprised people. Weren't previous MoOs fully awarded at this point?

Posted by: Mariner9 Nov 3 2006, 06:48 PM

I haven't researched this, but I also thought that the MOs were just announced, and not awarded study money.

Still, 250K for study isn't all that much.... that's something on the order of 2-3 man years (or, I suppose, 5-10 grad-student years, since they pay those folk dirt).

Posted by: volcanopele Nov 3 2006, 07:26 PM

Are EPOHc and DIXI (clever rolleyes.gif ) necessarily mutually exclusive? Is it possible both could be approved, with DI targeted to a new comet and "EPOHc" running during the "dead" time before and after the comet encounter?

Posted by: djellison Nov 3 2006, 08:37 PM

That's what I was wondering - will an observation program during cruise consume fuel to a point that might leave little or no margin for the DIXI encounter?

Doug

Posted by: elakdawalla Nov 3 2006, 09:58 PM

QUOTE (Comga @ Nov 2 2006, 08:42 PM) *
Generally correct. It can take long sequences of small images taken rapidly. In addition, the blur, while not originally intentional, would be a benfit here. It will spread the star light out so that the detector can use much longer exposures with much improved radiometry...

Comga's right here. I asked for an explanation from Drake Deming, the PI, and that's pretty much what he said; see the blog entry...
http://www.planetary.org/blog/article/00000756/

--Emily

Posted by: Comga Nov 4 2006, 06:16 AM

QUOTE (volcanopele @ Nov 3 2006, 12:26 PM) *
Are EPOHc and DIXI (clever rolleyes.gif ) necessarily mutually exclusive? Is it possible both could be approved, with DI targeted to a new comet and "EPOHc" running during the "dead" time before and after the comet encounter?


Yes they are. EPOCh can observe practically any time. DIXI needs to target the spacecraft for Earth fly-by and then observe Comet Boethin for a few months. Having already done the bulk of the retargeting just after the flyby of Tempel 1, there is not that much velocity change needed for DIXI, and EPOCh shouln't take much propellant at all. Other than that, as long as nothing wears out, they don't interfere with each other, and the two should cost less than the sum of the separate programs. You only have to wake up and check out the spacecraft once. The spacecraft was healthy last time it was contacted.

Posted by: stevesliva Nov 7 2006, 08:37 PM

QUOTE (Comga @ Nov 4 2006, 01:16 AM) *
Yes they are.

Don't you mean, no they're not mutually exclusive?

Posted by: Comga Nov 8 2006, 02:31 AM

QUOTE (stevesliva @ Nov 7 2006, 01:37 PM) *
Don't you mean, no they're not mutually exclusive?


OOPS! You are right. I did mean that DIXI and EPOCh are complimentary, not mutually exclusive. Running one program makes running the other easier, and there is no need to overlap the observation times.

As for djellision's question:
From what I know, the fuel usage for a few months of observation would be small, and there should be more than sufficient fuel margin for that and the Boethin encounter. IIRC, the maneuvers for Deep Impact used less fuel than planned, and much less than allotted, so there was significant fuel even after the July 2005 course adjustment. Does anyone here have those fuel budget numbers?

Posted by: Oren Iishi Jan 23 2007, 01:07 AM

I'm not really sure where to put this topic but does anyone know if the jammed Stardust camera filter wheel issue has been resolved? And if it isn't fixed yet, will that hinder the proposed Stardust extended mission? Thanks for any replies.

Posted by: AlexBlackwell Jan 23 2007, 01:22 AM

QUOTE (Oren Iishi @ Jan 22 2007, 03:07 PM) *
I'm not really sure where to put this topic but does anyone know if the jammed Stardust camera filter wheel issue has been resolved? And if it isn't fixed yet, will that hinder the proposed Stardust extended mission? Thanks for any replies.

Proposers for this AO were http://discovery.larc.nasa.gov/PDF_FILES/Discovery1.pdf that the "Stardust Imaging Camera (SIC) filter wheel [was] stuck in the broad-band position." Therefore, proposers had to take this into account when submitting proposals.

As far as I know, this hasn't changed.

Posted by: AlexBlackwell May 23 2007, 11:17 PM

http://www.news.cornell.edu/stories/May07/veverka.stardust.html
By Lauren Gold
Cornell University Chronicle Online
May 23, 2007

Posted by: Comga May 24 2007, 09:48 PM

How woud it be possible for them to target the fly-by so that the Deep Impact crater was near local noon? (All of the animations show it this way.) IIRC, there was still some uncertainty as to the rotation period, which can never be known well enough to pick a "phase" after six years. Do they plan to use the light curve to determine rotation? Tempel 1 is pretty close to spherical, making the light curve very hard to detect. If they were to try this, how much delay or advance could they get for 20kg of propellant?

If they can't target the proper phase or sub-solar longitude, they wil have 50/50 chance of seeing the crater at all. Half the surface is dark.

Posted by: Mariner9 Nov 2 2007, 03:12 PM

OK, we are now a year after the initial down-select to three proposals. If I recall correctly, oh, sorry... IIRC there were supposed to be about 9 months of detailed study, and then 3 months of review at NASA headquarters.

So any word on when a decision might come down?

Posted by: stevesliva Nov 2 2007, 06:00 PM

I seem to recall that all three were approved.

Yup, In July: http://www.msnbc.msn.com/id/19589401
http://www.unmannedspaceflight.com/index.php?showtopic=4370

Posted by: Mariner9 Nov 4 2007, 10:05 PM

QUOTE (stevesliva @ Nov 2 2007, 10:00 AM) *
I seem to recall that all three were approved.




No, sorry if I was unclear. The missions of opportunity were indeed approved.

But there were three proposals selected for furthur study for a full Discovery mission: an asteroid sample return, a Venus orbiter, and a lunar orbiter.

I'm wondering what became of those.

Posted by: vjkane Nov 5 2007, 04:32 AM

QUOTE (Mariner9 @ Nov 4 2007, 10:05 PM) *
No, sorry if I was unclear. The missions of opportunity were indeed approved.

But there were three proposals selected for furthur study for a full Discovery mission: an asteroid sample return, a Venus orbiter, and a lunar orbiter.

I'm wondering what became of those.


I recall reading that the selection of the next full mission will be announced in December.

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