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Nasa Picks "juno" As Next New Frontiers Mission
Guest_BruceMoomaw_*
post Jun 1 2005, 10:10 PM
Post #1





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http://www.nasa.gov/home/hqnews/2005/jun/H...rontiers_2.html

Yeah, I know it ain't Saturn, but we don't seem to have any proper slot for Jovian news -- including yesterday's totally unexpected announcement that Amalthea's density is so low as to suggest that it's a highly porous ice object; maybe a captured Kuiper Belt Object reduced to rubble by infalling meteoroids. As Jason Perry says, this might explain those previously mysterious light-colored patches on Amalthea -- they may be its underlying ice, exposed by impacts that punched through the layer of sulfur spray-painted onto it by Io.

Scott Bolton has been pretty talkative to me already about the design of Juno. It certainly won't be as good in the PR department as Galileo or Cassini, but it DOES carry a camera -- as much for PR as for Jovian cloud science, according to Bolton. And since the latitude of periapsis of its highly elliptical orbit will change radically during the primary mission, I wonder if they might be able to set up at least one close photographic flyby of Io and/or Amalthea? (I believe, by the way, that this selection is a bit ahead of schedule -- and it certainly indicates that NASA's science program under Griffin won't be a complete slave to Bush's Moon-Mars initiative.)
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Guest_BruceMoomaw_*
post Jun 17 2005, 12:25 AM
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You'll notice that I HAVE backtracked from the Io Observer having "a good chance of being flown in the early 2020s" to "a real chance of being flown before the end of the 2020s" -- having now considered the implications of the newly announced stretchout in the New Frontiers schedule. But beyond that, I refuse to retreat.
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Guest_vjkane2000_*
post Jun 17 2005, 02:55 AM
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QUOTE (BruceMoomaw @ Jun 16 2005, 05:25 PM)
You'll notice that I HAVE backtracked from the Io Observer having "a good chance of being flown in the early 2020s" to "a real chance of being flown before the end of the 2020s" -- having now considered the implications of the newly announced stretchout in the New Frontiers schedule.  But beyond that, I refuse to retreat.
*


By the end of the 2020s, I'll be 75. I'd rather not wait that long, so I'm hoping for a Discovery-class mission to be proposed and accepted. One, called Volcan, was written up several years ago.

One can imagine what such a mission might look like:

Solar powered.
Number of encounters would be limited by cumulative radiation dose. Galileo experienced ~40Krad per encounter. The solar panels will likely be the limiting factor in the number of enounters. I'm not sure how quickly they degrade. The Volcan proposal include something like 3-5 enounters. Perhaps that can be stretched a bit, and/or the radiation per orbit lessened by choosing an encounter point or orbit inclination to minimize radiation.

The instrument compliment could be pretty simple: The Deep Impact Hi-Res and medium-res camera with visible imagers and near-IR spectrometers. A radiometer would need to also use the Hi-Res optics (possibly replacing the near-IR spectrometer). If the encounters will be very close, then a magnetometer would be nice.

The mission would include as many close encounters as the radiation limit will allow (probably at least 5, maybe 10?) spaced 1 or more months apart to allow time series studies of changes. After that limit is reached, perijove would be raised to a safe distance to allow continued observations from a distance (which is why I'd like to see something with the optical capabilities of the Deep Impact Hi-Res on the craft). Long distance time studies would continue as long as funding would allow. During this phase, observations of Jupiter or encounters with Ganymede or Callisto (radiation at Europa is too high) could be possible, but add to mission complexity and cost.
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JRehling
post Jun 17 2005, 04:19 PM
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QUOTE (vjkane2000 @ Jun 16 2005, 07:55 PM)
The mission would include as many close encounters as the radiation limit will allow (probably at least 5, maybe 10?) spaced 1 or more months apart to allow time series studies of changes.  After that limit is reached, perijove would be raised to a safe distance to allow continued observations from a distance (which is why I'd like to see something with the optical capabilities of the Deep Impact Hi-Res on the craft).
*


A difficulty with eccentric orbit orbiters that zoom in to observe inner satellites at periapsis only is that if the mission is not very long, you observe only a limited range of lighting conditions, and with tidally-locked rotations, you observe a limited range of longitudes. This is why we've seen one side of Io much better than the other (from Galileo) and keep seeing similar longitudes of Titan -- even as late as next spring, we still won't have decent coverage of all Titan longitudes, despite many flybys.

If an orbiter could go into an eccentric polar orbit around Jupiter, it might be able to observe Io (or Europa) both coming and going (when the satellite is nearer to the Sun than Jupiter, or farther). But that's not going to be cheap in delta-v.

I'm not sure what tradeoffs are possible, but getting multiple close flybys of the same hemisphere doesn't get you a lot that a single flyby doesn't. (See Mariner 10.) Of course, the long-duration observations from farther out are all fine and good.

I'll chime in that the capability for continuous observation of Io, at least to the point of observing the several larger hotspots, from Earth had gotten pretty good, although I'm not aware of the details of any such surveys that may be ongoing.
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Posts in this topic
- BruceMoomaw   Nasa Picks "juno" As Next New Frontiers Mission   Jun 1 2005, 10:10 PM
- - tedstryk   Great to hear. With the whole lunar program being...   Jun 1 2005, 10:44 PM
- - djellison   I take it this puts to bed the possibility of an N...   Jun 1 2005, 10:45 PM
- - Sunspot   Any proposals on what kind of camera?   Jun 1 2005, 11:39 PM
- - BruceMoomaw   No website yet, and I have no details on what kind...   Jun 1 2005, 11:51 PM
- - BruceMoomaw   Postscript: the mission selection actually was pla...   Jun 1 2005, 11:51 PM
- - Sunspot   They can't return to Jupiter without taking a ...   Jun 1 2005, 11:57 PM
- - edstrick   Atmosphere sounding instruments can also return ve...   Jun 2 2005, 06:49 AM
- - BruceMoomaw   Well, I can give you the full instrument list (alt...   Jun 2 2005, 10:37 AM
|- - garybeau   I would have thought / hoped the next Jovian missi...   Jun 2 2005, 12:39 PM
|- - tty   QUOTE (garybeau @ Jun 2 2005, 02:39 PM)I woul...   Jun 2 2005, 04:40 PM
|- - volcanopele   QUOTE (garybeau @ Jun 2 2005, 05:39 AM)I woul...   Jun 2 2005, 05:51 PM
|- - JRehling   QUOTE (garybeau @ Jun 2 2005, 05:39 AM)I woul...   Jun 6 2005, 03:26 PM
|- - tedstryk   I think the six-flybys analogy is a good one (seve...   Jun 6 2005, 05:02 PM
|- - Bjorn Jonsson   I vaguely remember reading somewhere that Juno wil...   Jun 6 2005, 05:26 PM
- - Chmee   Hopefully Juno wont have an umbrella style high ga...   Jun 2 2005, 03:03 PM
- - BruceMoomaw   Well, the Decadal Survey recommended -- and the ne...   Jun 3 2005, 01:17 AM
|- - Gsnorgathon   QUOTE (BruceMoomaw @ Jun 3 2005, 01:17 AM)......   Jun 3 2005, 02:16 AM
|- - Redstone   QUOTE (Gsnorgathon @ Jun 3 2005, 02:16 AM)Are...   Jun 3 2005, 02:32 PM
|- - Gsnorgathon   QUOTE (Redstone @ Jun 3 2005, 02:32 PM)... if...   Jun 3 2005, 09:58 PM
|- - garybeau   QUOTE The Jupiter icy moons' orbiter mission w...   Jun 4 2005, 12:18 PM
|- - tedstryk   I don't think getting to Europa is the biggest...   Jun 4 2005, 12:27 PM
- - BruceMoomaw   Jason is likely to be disappointed if he thinks of...   Jun 3 2005, 01:21 AM
|- - volcanopele   I never thought it would actually flyby Io, given ...   Jun 3 2005, 01:35 AM
|- - um3k   QUOTE (BruceMoomaw @ Jun 2 2005, 09:21 PM)it ...   Jun 4 2005, 02:38 AM
- - BruceMoomaw   BESIDES all that, there was one other major proble...   Jun 3 2005, 10:57 PM
- - edstrick   The Juno instrument selection looks quite "re...   Jun 4 2005, 09:04 AM
- - edstrick   Most of the P.R. talk on crashing Galileo into Jup...   Jun 5 2005, 01:56 AM
- - Decepticon   QUOTE ALL THESE WORLDS ARE YOURS EXCEPT EUROPA ATT...   Jun 5 2005, 03:29 AM
- - BruceMoomaw   I don't think the crashing of Galileo to ...   Jun 5 2005, 06:23 AM
|- - dvandorn   The other real difference between potential Martia...   Jun 5 2005, 09:30 AM
|- - garybeau   QUOTE (BruceMoomaw @ Jun 5 2005, 01:23 AM)Tha...   Jun 6 2005, 12:55 AM
|- - JRehling   Three miscellaneous comments for this thread, from...   Jun 6 2005, 01:30 AM
- - BruceMoomaw   QUOTE (edstrick @ Jun 5 2005, 01:56 AM)Most o...   Jun 5 2005, 06:32 AM
- - BruceMoomaw   While the new Solar System Roadmap (or, rather its...   Jun 5 2005, 06:53 AM
|- - tedstryk   QUOTE (BruceMoomaw @ Jun 5 2005, 06:53 AM)But...   Jun 5 2005, 10:35 AM
|- - Stephen   QUOTE (BruceMoomaw @ Jun 5 2005, 06:53 AM)But...   Jun 8 2005, 09:52 AM
- - BruceMoomaw   QUOTE (edstrick @ Jun 4 2005, 09:04 AM)The Ju...   Jun 5 2005, 07:09 AM
|- - tedstryk   QUOTE (BruceMoomaw @ Jun 5 2005, 07:09 AM)...   Jun 5 2005, 10:32 AM
- - Redstone   QUOTE (garybeau @ Jun 4 2005, 12:18 PM)The or...   Jun 6 2005, 02:17 AM
|- - Bob Shaw   Some comments on life on Mars (and elsewhere) and ...   Jun 6 2005, 01:58 PM
- - BruceMoomaw   Yeah, it will be -- which will certainly interfere...   Jun 6 2005, 07:27 PM
- - Myran   dvandorn wrote: "I think the most boring thi...   Jun 8 2005, 12:12 PM
|- - JRehling   QUOTE (Myran @ Jun 8 2005, 05:12 AM)As for sa...   Jun 8 2005, 04:47 PM
- - Decepticon   They are sending a Probe to Jupiter and according ...   Jun 10 2005, 02:03 AM
|- - JRehling   QUOTE (Decepticon @ Jun 9 2005, 07:03 PM)They...   Jun 10 2005, 04:30 PM
|- - tedstryk   Another factor to consider is that a decent Europa...   Jun 10 2005, 04:55 PM
- - Gsnorgathon   FWIW, a wee writeup at Astrobio.net, and the ever-...   Jun 10 2005, 05:30 AM
- - edstrick   Part of the problem is that *any* Europa orbiter m...   Jun 11 2005, 12:16 AM
|- - Decepticon   Even with Galileo type flybys would make me happy....   Jun 11 2005, 02:37 AM
- - Phil Stooke   Ted, I missed your Amalthea images until just now ...   Jun 11 2005, 03:21 AM
|- - tedstryk   QUOTE (Phil Stooke @ Jun 11 2005, 03:21 AM)Te...   Jun 11 2005, 03:30 AM
- - BruceMoomaw   Juno's orbit will go from only 4500 km above J...   Jun 11 2005, 09:04 PM
|- - MiniTES   QUOTE (BruceMoomaw @ Jun 11 2005, 09:04 PM)Ju...   Jun 15 2005, 02:51 PM
- - Phil Stooke   Spinning doesn't have to mean Pioneer 10-class...   Jun 15 2005, 03:28 PM
- - Decepticon   Can Juno at least take Movie like animations of th...   Jun 15 2005, 08:17 PM
- - BruceMoomaw   According to the Space.com article, it will indeed...   Jun 15 2005, 10:17 PM
- - BruceMoomaw   "...rathern using a filter wheel" is rea...   Jun 15 2005, 10:19 PM
- - Sunspot   Oh... thats a shame, I guess we probably wont ever...   Jun 15 2005, 10:46 PM
- - Phil Stooke   Actually we will see some good stuff in 2007 from ...   Jun 15 2005, 11:26 PM
- - edstrick   Why is it spinning? Field and Particles instrument...   Jun 15 2005, 11:27 PM
- - BruceMoomaw   Fear not! We WILL see excellent images of Jup...   Jun 16 2005, 02:26 AM
- - BruceMoomaw   Footnote: the reason that the radiation dose for a...   Jun 16 2005, 02:38 AM
|- - MiniTES   QUOTE (BruceMoomaw @ Jun 16 2005, 02:38 AM)Fo...   Jun 16 2005, 05:20 PM
|- - djellison   QUOTE (MiniTES @ Jun 16 2005, 05:20 PM)How th...   Jun 16 2005, 06:25 PM
- - edstrick   And.... It's moving perpendicular to the belts...   Jun 16 2005, 05:43 AM
- - BruceMoomaw   It would be more accurate to say that they intend ...   Jun 16 2005, 07:44 AM
- - Analyst   Bruce, I want your optimism when it comes to futur...   Jun 16 2005, 12:34 PM
|- - JRehling   QUOTE (Analyst @ Jun 16 2005, 05:34 AM)Bruce,...   Jun 16 2005, 01:53 PM
- - BruceMoomaw   Yup -- they've had solar panels planned for a ...   Jun 17 2005, 12:08 AM
- - BruceMoomaw   QUOTE (Analyst @ Jun 16 2005, 12:34 PM)Bruce,...   Jun 17 2005, 12:21 AM
- - BruceMoomaw   You'll notice that I HAVE backtracked from the...   Jun 17 2005, 12:25 AM
|- - vjkane2000   QUOTE (BruceMoomaw @ Jun 16 2005, 05:25 PM)Yo...   Jun 17 2005, 02:55 AM
|- - JRehling   QUOTE (vjkane2000 @ Jun 16 2005, 07:55 PM)The...   Jun 17 2005, 04:19 PM
|- - vjkane2000   QUOTE (JRehling @ Jun 17 2005, 09:19 AM)A dif...   Jun 17 2005, 05:23 PM
- - BruceMoomaw   It's a possibility -- but I suspect you're...   Jun 17 2005, 07:17 AM
|- - gpurcell   QUOTE (BruceMoomaw @ Jun 17 2005, 07:17 AM)In...   Jun 17 2005, 07:39 PM
- - edstrick   You really *do* want a very high power telescopic ...   Jun 17 2005, 07:22 AM
- - BruceMoomaw   Turns out I misread that white paper -- Europa Orb...   Jun 17 2005, 07:22 AM
- - vjkane2000   Cost is, of course, a major issue for any Jupiter ...   Jun 17 2005, 02:00 PM
- - BruceMoomaw   Damned if I know, especially with this president -...   Jun 19 2005, 10:29 PM
|- - Bob Shaw   Bruce: Are you talking about the Hubble II comple...   Jun 19 2005, 10:47 PM
- - BruceMoomaw   As for Van Kane's comments on the "Io Obs...   Jun 19 2005, 10:58 PM
|- - JRehling   Imagine the way Halley's Comet's orbi...   Jun 20 2005, 01:25 AM
- - BruceMoomaw   "Are you talking about the Hubble II complete...   Jun 19 2005, 11:54 PM
- - BruceMoomaw   (1) "Imagine the way Halley's Comet...   Jun 20 2005, 02:55 AM
|- - JRehling   QUOTE (BruceMoomaw @ Jun 19 2005, 07:55 PM)Ah...   Jun 20 2005, 08:55 PM
- - gpurcell   I've always thought that the best deorbit miss...   Jun 20 2005, 03:09 PM
- - BruceMoomaw   Actually, there are a hell of a lot of things they...   Jun 21 2005, 12:31 PM
|- - JRehling   QUOTE (BruceMoomaw @ Jun 21 2005, 05:31 AM)Ac...   Jun 21 2005, 03:31 PM
|- - vjkane2000   QUOTE (JRehling @ Jun 21 2005, 08:31 AM)Indee...   Jun 22 2005, 09:10 AM
- - BruceMoomaw   Well, keep in mind that Cassini's 45 close fly...   Jun 22 2005, 10:52 PM
- - BruceMoomaw   The presentations from the June OPAG meeting are n...   Jun 29 2005, 06:02 PM
|- - imran   Thanks for the links, Bruce. I am surprised too t...   Jun 29 2005, 08:37 PM
- - BruceMoomaw   This hardly means that they're not considering...   Jun 29 2005, 10:28 PM
- - BruceMoomaw   And, for one recent JPL study of a Titan aerobot m...   Jun 29 2005, 10:31 PM
|- - JRehling   QUOTE (BruceMoomaw @ Jun 29 2005, 03:31 PM)An...   Jun 30 2005, 05:20 PM
- - BruceMoomaw   Actually, we DO need more surface observation poin...   Jun 30 2005, 06:50 PM
- - tedstryk   QUOTE (BruceMoomaw @ Jun 30 2005, 06:50 PM)Ac...   Jun 30 2005, 06:58 PM
- - JRehling   QUOTE (BruceMoomaw @ Jun 30 2005, 11:50 AM)Ac...   Jun 30 2005, 07:15 PM
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