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Nasa Picks "juno" As Next New Frontiers Mission
Gsnorgathon
post Jun 10 2005, 05:30 AM
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FWIW, a wee writeup at Astrobio.net, and the ever-popular "artist's conception" of the spacecraft. Solar!
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JRehling
post Jun 10 2005, 04:30 PM
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QUOTE (Decepticon @ Jun 9 2005, 07:03 PM)
They are sending a Probe to Jupiter and according to this article Europa Ganymede and Callisto will not be studied?!?!
EUROPA should be Number 1 on the priority list.
I'm so upset by this article. http://www.space.com/searchforlife/seti_juno_050609.html
*


For some reason, I can't load that article. I get a blank screen.

But, the reason why Europa has been shortchanged is organizational fumbling of a high degree. I can remember when Pluto and Europa were competing for a launch date that would have already taken place, and the winner of the competition was... neither.
Europa Screw-up #1 was to bundle three bizarrely dissimilar missions under a single planning structure (a Europa orbiter, a Pluto flyby, and a solar probe), even though the three had little in common except they were spacecraft that would not land anywhere.
Europa Screw-up #2 was to propose JIMO, aka Mission Impossible, so that we had to wait until it fell back to the ground when the gravity of common sense had counteracted the upward momentum of bad politics. JIMO was meant to be the sugarcoating on an expensive nuclear propulsion research program, which was motivated by a way to drain NASA funding for a quasi-military project. JIMO's math never worked, and it was the brainchild of people who don't care if the math works before they sic some government agencies on a job.
As far as Europa was concerned, the JIMO proposal was an X year delay, with X being mercifully hastened by O'Keefe's departure.

As it turns out, a few years ago was probably too early to have commited to a Europa mission design. It's taken a while for Galileo results to be digested, and even now, I think a Europa exploration architecture has to be considered very carefully. We're playing 20 questions with Europa, where each question costs a billion dollars or so. The best next mission to Europa might not be the best mission if we were only sending a total of one. We've got to consider what the next mission would be depending upon the first one, and then plan to make absolutely sure that no mission asks a yes/no question where the answer is, "Neither yes nor no. That's the wrong question."

It's clear that Juno is a good Jupiter mission and it can go ahead and take place. Waiting for the Europa situation to clarify before sending a mission to Jupiter is like waiting to figure out next year's taxes before eating breakfast. The two things are unrelated. Europa shouldn't preempt a good Jupiter mission any more than Europa should preempt a good Mercury mission.
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tedstryk
post Jun 10 2005, 04:55 PM
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Another factor to consider is that a decent Europa Orbiter mission probably can't be done as a New Frontiers mission. Juno will allow some fundamental Jovian science to be accomplished. And it is one of the most productive missions that can be accomplished at Jupiter on such a budget.


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edstrick
post Jun 11 2005, 12:16 AM
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Part of the problem is that *any* Europa orbiter mission is ***HARD***.
It takes a tremendous amount of Delta-V (velocity change) and only some of that can be done by gravity assist flyby's of the moons. Add to that the radiation environment that was crippling and killing Galileo as the extended missions proceeded, but on a continuous basis as you get in toward Europa, rather for only the periapsis pass part of month long orbits. You need extra radiation hardened electronics, AND massive shielding. The original Europa orbiter mission was nuked as it's projected costs passed some 1.2 billion, heading for and past 1.5 billion <or so>, when it was supposed to be an under 1 billion $ mission.

Good management and realistic objectives will help tremendously, but they won't solve the basic problem. It's a damn hard mission.
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Decepticon
post Jun 11 2005, 02:37 AM
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Even with Galileo type flybys would make me happy. From the sounds of the space.com article Juno will not get that far out?!
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Phil Stooke
post Jun 11 2005, 03:21 AM
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Ted, I missed your Amalthea images until just now - they are very nice. I think I recall a similar multispectral sequence of Thebe... would be interesting to see it.

Phil


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tedstryk
post Jun 11 2005, 03:30 AM
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QUOTE (Phil Stooke @ Jun 11 2005, 03:21 AM)
Ted, I missed your Amalthea images until just now - they are very nice.  I think I recall a similar multispectral sequence of Thebe... would be interesting to see it. 

Phil
*


I am planning to work on that. I am also trying to create a "mask" for the E26 image based on color data from other orbits.


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Guest_BruceMoomaw_*
post Jun 11 2005, 09:04 PM
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Juno's orbit will go from only 4500 km above Jupiter's 1-bar air pressure level (it will be even closer to the tops of the ammonia clouds) all the way out to 30 Jupiter radii from the planet. (They need to get that close to ensure really high-resolution gravity and magnetic maps of Jupiter -- it's the same orbit planned for the "INSIDE Jupiter" mission that was a Discovery finalist twice and has now been combined with two other Jovian Discovery proposals to create Juno.)

That periapsis will wander somewhat in latitude, although I haven't got specific figures yet -- but I believe it's enough to theoretically allow flybys of any mooon out to Callisto. PI Scott Bolton tells me that there are currently no plans for flybys of any of the moons (although, during our previous conversations, he had expressed some interest in the idea during the extended mission); but the description in Space.com says that Juno's camera may be used for longer-distance photos of Io and Amalthea.

It's important to remember that this mission has radically different goals from any mission to study Europa or the other moons -- its purpose is to study JUPITER, by God, and specifically its composition and the size of its rock/ice core, which are extremely important in answering questions about how the giant planets actually formed. (This is one of the most important questions for planetary scientists right now, and there are two radically different theories.) Also Jupiter's polar magnetosphere, which the NASA's Sun-Solar Systems Directorate -- separately from its Solar System Directorate -- has also declared to be an extremely important short-term goal for its own researches and worthy of a mission. To achieve all this, it needs an orbit completely different from those that would be used by a moon-studying orbiter -- and since such a mission is also simpler and cheaper, they decided, entirely logically, to fly it first.

As for the Europa mixup, John Rehling doesn't mention the biggest villain of all: Dan Goldin, aka "Captain Crazy". NASA's science advisory board recommended officially -- and entirely sensibly -- that a Pluto mission, which required no new technology at all, should be flown BEFORE the Europa Orbiter, and specifically in 2003. Dan Goldin, however, was determined to reverse their order because of his personal obsession with astrobiology at all costs -- "Nobody gives a damn about Pluto", he told his staffers. (His repeated urgings that NASA should use radically new technologies, entirely unnecessarily, to build a teeny-weeny Pluto probe --"the size of my fist", to quote one disgruntled researcher -- were, as he privately told his staffers, just a cover for the fact that he intended to kill the Pluto mission completely.)

The result, given the very real and major new technological difficulties in flying a Europa Orbiter, were that we didn't get either mission -- or rather that the Pluto mission was delayed until 2006 and finally rammed through by Congress over the dead bodies of Goldin, Sean O'Keefe and President Bush, which means both a more expensive Pluto mission and a distinctly scientifically inferior one to what we would have had had it been launched in 2003 or 2004. The case for such a mission, both scientifically and fiscally, was so strong that even the GOP Congress was finally firmly convinced of the idiocy of not flying it. (To my continuing amazement, I myself ended up playing a significant role in getting that decision made -- largely due to a SpaceDaily article I published in 2000 pointing out that either the Stardust or CONTOUR comet probe could be easily redesigned to fly a Pluto mission cheaply -- which is why I have a free ticket to its launch next January. No doubt other people had come up with the same idea; but Goldin, it later turned out, had been threatening to cut off their grants if they didn't keep their mouths shut. They had no such leverage over me, and so I ended up -- entirely accidentally -- belling the cat. But I digress.)

Anyway, as a result of Goldin's monomania, we ended up getting both a Pluto mission later and worse and more expensive than we could have had it, but also probably some unnecesary delays to Europa Orbiter -- which were then made worse by the fact that O'Keefe, due to his total lack of engineering training, fell for the cretinous JIMO scheme to fly a nuclear-powered battleship to Jupiter, even though the science community had officially stated that it didn't want it. (In this respect, as in many others, he got rolled by his unscrupulous NASA underlings; but one scientist has told me that O'Keefe's nuclear-enthusiast brother also helped talk him into it.) Now -- years later than we could have been -- we're back to Square One where Europa Orbiter is concerned.

What Ed Strick says is also true: the first version of Europa Orbiter was cancelled becuase it had a $1 billion cost cap, which simply could not be met. Now NASA's new Solar System Roadmap calls for it to be the first of the new class of "Small Flagship" Solar System mission -- costing between $700 million and $ 1.5 billion -- to be launched at 5-year intervals. Europa Orbiter is recommended for launch in 2014 (and it looks more and more as though the ESA will collaborate with us on it). The second Small Flagship is likely to be to Titan in 2019, and the third to Venus in 2024.
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MiniTES
post Jun 15 2005, 02:51 PM
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QUOTE (BruceMoomaw @ Jun 11 2005, 09:04 PM)
Juno's orbit will go from only 4500 km above Jupiter's 1-bar air pressure level (it will be even closer to the tops of the ammonia clouds) all the way out to 30 Jupiter radii from the planet.  (They need to get that close to ensure really high-resolution gravity and magnetic maps of Jupiter -- it's the same orbit planned for the "INSIDE Jupiter" mission that was a Discovery finalist twice and has now been combined with two other Jovian Discovery proposals to create Juno.) 

That periapsis will wander somewhat in latitude, although I haven't got specific figures yet -- but I believe it's enough to theoretically allow flybys of any mooon out to Callisto.  PI Scott Bolton tells me that there are currently no plans for flybys of any of the moons (although, during our previous conversations, he had expressed some interest in the idea during the extended mission); but the description in Space.com says that Juno's camera may be used for longer-distance photos of Io and Amalthea.

It's important to remember that this mission has radically different goals from any mission to study Europa or the other moons -- its purpose is to study JUPITER, by God, and specifically its composition and the size of its rock/ice core, which are extremely important in answering questions about how the giant planets actually formed.  (This is one of the most important questions for planetary scientists right now, and there are two radically different theories.)  Also Jupiter's polar magnetosphere, which the NASA's Sun-Solar Systems Directorate -- separately from its Solar System Directorate -- has also declared to be an extremely important short-term goal for its own researches and worthy of a mission.  To achieve all this, it needs an orbit completely different from those that would be used by a moon-studying orbiter -- and since such a mission is also simpler and cheaper, they decided, entirely logically, to fly it first.

As for the Europa mixup, John Rehling doesn't mention the biggest villain of all: Dan Goldin, aka "Captain Crazy".  NASA's science advisory board recommended officially -- and entirely sensibly -- that a Pluto mission, which required no new technology at all, should be flown BEFORE the Europa Orbiter, and specifically in 2003.  Dan Goldin, however, was determined to reverse their order because of his personal obsession with astrobiology at all costs -- "Nobody gives a damn about Pluto", he told his staffers.  (His repeated urgings that NASA should use radically new technologies, entirely unnecessarily, to build a teeny-weeny Pluto probe --"the size of my fist", to quote one disgruntled researcher -- were, as he privately told his staffers, just a cover for the fact that he intended to kill the Pluto mission completely.) 

The result, given the very real and major new technological difficulties in flying a Europa Orbiter, were that we didn't get either mission -- or rather that the Pluto mission was delayed until 2006 and finally rammed through by Congress over the dead bodies of Goldin, Sean O'Keefe and President Bush, which means both a more expensive Pluto mission and a distinctly scientifically inferior one to what we would have had had it been launched in 2003 or 2004.  The case for such a mission, both scientifically and fiscally, was so strong that even the GOP Congress was finally firmly convinced of the idiocy of not flying it.  (To my continuing amazement, I myself ended up playing a significant role in getting that decision made -- largely due to a SpaceDaily article I published in 2000 pointing out that either the Stardust or CONTOUR comet probe could be easily redesigned to fly a Pluto mission cheaply -- which is why I have a free ticket to its launch next January.  No doubt other people had come up with the same idea; but Goldin, it later turned out, had been threatening to cut off their grants if they didn't keep their mouths shut.  They had no such leverage over me, and so I ended up -- entirely accidentally -- belling the cat.  But I digress.) 

Anyway, as a result of Goldin's monomania, we ended up getting both a Pluto mission later and worse and more expensive than we could have had it, but also probably some unnecesary delays to Europa Orbiter -- which were then made worse by the fact that O'Keefe, due to his total lack of engineering training, fell for the cretinous JIMO scheme to fly a nuclear-powered battleship to Jupiter, even though the science community had officially stated that it didn't want it.  (In this respect, as in many others, he got rolled by his unscrupulous NASA underlings; but one scientist has told me that O'Keefe's nuclear-enthusiast brother also helped talk him into it.)  Now -- years later than we could have been -- we're back to Square One where Europa Orbiter is concerned. 

What Ed Strick says is also true:  the first version of Europa Orbiter was cancelled becuase it had a $1 billion cost cap, which simply could not be met.  Now NASA's new Solar System Roadmap calls for it to be the first of the new class of "Small Flagship" Solar System mission -- costing between $700 million and $ 1.5 billion -- to be launched at 5-year intervals.  Europa Orbiter is recommended for launch in 2014 (and it looks more and more as though the ESA will collaborate with us on it).  The second Small Flagship is likely to be to Titan in 2019, and the third to Venus in 2024.
*


Why is it spinning? Granted, the science to be done doesn't require imaging, but you CAN do some really good science with cameras. Recall the differences in what we learned between Pioneer and Voyager, much of which was due to the fact that Voyager had a camera. How much more would it cost to build a three-axis stabilized craft? If it is spinning, are our computer processing techniques good enough to reconstruct images better than we could with Pioneer. Or can I say the magic words "scan platform".... wink.gif

Who will be in charge of building the small flagships? Are these going to be MRO-class missions, or more like Discovery missions to the outer planets? I'm assuming Juno will have some RTGs to play with? What does the instrumentation look like on the possible Europa orbiter? It needs a radar, and of course a camera.


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Phil Stooke
post Jun 15 2005, 03:28 PM
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Spinning doesn't have to mean Pioneer 10-class imaging. For one thing we are decades on in technological development! A modern push-broom scanner could produce very high quality images from a spinning platform, and if the thing can be tilted in the plane of the rotation axis it can have quite a range of viewing angles. Giotto imaged like this, albeit with a dinky little detector (sorry, Uwe) - but it could be done very well today.

I am also one of those who long for high resolution images of Amalthea.

Phil


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Decepticon
post Jun 15 2005, 08:17 PM
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Can Juno at least take Movie like animations of the atmosphere?

This was something I was looking forward to on the Galileo mission until the antenna flop.
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Guest_BruceMoomaw_*
post Jun 15 2005, 10:17 PM
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According to the Space.com article, it will indeed take some movies of cloud patterns -- although I don't know how many there will be. (It's important to keep in mind that Juno's com rate will be much lower than Galileo's was planned to be; and images require MUCH more bits than any other type of data the craft will send.)

I've recently learned that the camera will be a slightly modified version of the descent imager for the 2009 MSL -- which means it will take 2-D images instantanteously rather than using the one-line "pushbroom" technique, and that all three colors will be imaged simultaneously rathern using a filter wheel. This means that -- if the spacecraft's spin axis is simply pointed in the right direction -- it could take very rapid-fire images during a flyby of a Jovian moon, although it could store only a limited number of them. (In any case, Bolton tells me that there are currently no plans for moon flybys -- although he expressed some interest in the idea during our earlier conversations, and I think you might see it during an extended mission after the 32-orbit primary mission is over.)

Even a pushbroom camera on a spinning spacecraft, however, could take far better images than the instrument on Pioneer 10 and 11 -- which was simply a single light-meter, equipped with a filter wheel, which could record data during each of the craft's rotations and use (I believe) a tiltable mirror to build up a 2-D image -- VERY SLOWLY, since the Pioneers didn't spin that fast. (By contrast, a 1-line CCD array on a spinning craft can build up a high-res 2-D image during one single sweep of a spinning craft, if of course the CCD line is parallel to the craft's spin axis.) It took 40 minutes for the Pioneers just to build up a 200-line image, which by itself meant that the resolution was limited. It's important to keep in mind that the purpose of the Pioneers was just to serve as scouts of the environmental dangers that would be encountered by later, more advanced Jupiter craft -- dust in the Asteroid Belt, and the intensity of Jupiter's radiation belts -- and so they wer designed to be extremely simple and cheap, since fields and particles and dust detectors don't require complex pointing and have a low bit rate that doesn't require high-speed communcations or a tape recorder. Therefore, any additional science data from the Pioneers was regarded as gravy, and only a few simple instruments capable of working under those conditions were added: the Imaging Photopolarimeter, a UV photometer and an IR radiometer. (The images returned by the IPP, in fact, would have been regarded as successful even if their resolution was no better than that of Earth-based Jovian photos; the instrument's main purposes were to map zodiacal light and study the optical properties of Jupiter's clouds at sunlight angles unavailable from Earth.)
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Guest_BruceMoomaw_*
post Jun 15 2005, 10:19 PM
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"...rathern using a filter wheel" is really "...rather THAN using a filter wheel". *sigh*
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Guest_Sunspot_*
post Jun 15 2005, 10:46 PM
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Oh... thats a shame, I guess we probably wont ever see spectacular images of Jupiter like those from Galileo again in our lifetimes. sad.gif
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Phil Stooke
post Jun 15 2005, 11:26 PM
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Actually we will see some good stuff in 2007 from New Horizons.

Phil


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