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Space Science

Jupiter As From Cassini 98

ftyczka writes "NASA released Casssini's first image of Jupiter. The picture, and the caption is available online. "
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Jupiter As From Cassini

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  • No, but they have proved that there is metallic hydrogen there, which I think is much cooler anyways. You can find the article over at Scientific American [sciam.com]. I'm not sure when the result was published, but it is within a year and a half. Very neat quantum effects start happening with hydrogen when you get hydrogen under a couple of kilo-atmospheres.
  • by Masem ( 1171 ) on Monday October 09, 2000 @10:43AM (#720276)
    I looked at this picture, and being a chemical engineer, it's interesting as to why the gas giant forms 'rings' pararrel in global space to the equator of the planet. It's easily shown that if you spin a perfect sphere within an enclosed sphere, the gas between those two will form patterns as with Jupiter. As you start to 'roughen' the inner sphere, you begin to disrupt those patterns, and you'll get chaos in the patterns. If one could take a similar picture of earth, you'd expect to see the same, no horizontal bands of flow, but more turbulence.

    Of course, this effect ebbs as you increases the space between the sphere relative to the amount of roughness of the inner sphere. So (as it's predicted) Jupiter's got an inner core so small relative to the diameter of it's gas size, that any turbulence created just outside of the core will be nullified by the time you hit the visible part of the planet.

    But then why does the red spot persist? We've known about it for a couple of centuries, so if it were simply a local disruption from stability, it would have corrected itself by now, but everytime we look at it, it's about the same shape, size, color, and relative placement on the planet. Could there be something just beneath the layer of gases like a small moon that is dense enough to cause the red spot?

    I'm sure this questions have been thought of, but space is still the most interesting thing we have to look at nowadays...

  • I thought those might be from the Shoemaker-Levy 9 impact too, but after a little searching on the NASA website, it doesn't look to be the case. The impacts from the comet made dark dots on the surface, which then dissipated in a turbulent fashion. Not to mention, the impact occured "lower" than where the white dots are.

    a random Shoemaker-Levy impact image [nasa.gov]
  • The "controversy" was a couple wacko's from Greenpeace threatening to storm the launch pad and chain themselves to the rockets. They changed their minds since the Air Force guards were fully armed...

    --
  • I very much doubt they are leftover from SL9. AFAIK, the disruption from the comet disappeared after a few hours (or around that order of magnitude, anyway).
  • Holy crap! If they want to spend that amount of money on a stupid telecopie thing that goes out into space and shows us pictures of things that we have already seen before, they can go and keep the damn thing! If you can see Jupiter with your own telescope and didn't have to pay $92 mil, well your better than them!
  • Just taking the time to point out that this story was covered in detail at BottomQuark.com last Friday, 3 days before it made it to slashdot's readers. If you value your science, you should value your BottomQuark [bottomquark.com].

    OldSaxon [mailto]


    You like science?

  • by Mr. Slippery ( 47854 ) <tms&infamous,net> on Monday October 09, 2000 @12:19PM (#720282) Homepage
    Their general opinion was "nukes are bad, m-kay" ... but they managed to get a piece on 60 minutes as well.

    There were also several more articulate explanations of the dangers involved, such as this [animatedsoftware.com] or this [animatedsoftware.com].

    The risk was non-zero, and NASA does not have what I would call a good track record on risk estimation. (See Feyman's tale in "What Do You Care What Other People Think?") Yes, there was ignorance among many who opposed the lauch; there was also plenty of ignorance among many who supported it.

  • I agree it certainly should remind us of the vast beauty of the universe.

    Sometimes I get depressed when I see the idiocy of human life--as illustrated by recent events in Jerusalem, or Antwerp, for example. At those times, the vast scales required of the imagination by geology, planetary science and cosmology are somehow soothing and exhilirating. We may nuke ourselves tomorrow -- Jupiter will continue in its progress round the sun. Stars will still form in the nebulae of Orion... These thoughts somehow bring me peace.

  • Stuff like this should remind us all that there are bigger things, in size, mass, beauty and mystery out there. If we would just look outside of our sometimes narrow view of what we consider "important" we can see and appricate things like what Cassini can do for us now and for those in the future.

    Pictures like this make me hope that the world is still interested in discovery. Let the Cassini pictures and info roll on!
  • The quality of the image is impressive when you consider that the distance between the probe and Jupiter at the time the image was taken was about 1/3 of the distance between the Earth and the Sun. It's about as good as the best Earth-based images of Jupiter. If that is a test image, then the real images could be even better.

    --
  • The probability of an accident was low, but the potential loss of life of that hypothtical accident was high, hence the legitimate concern.

    The potential loss of life is essentially zero, since there's no plausible way that the RTG fuel capsule can be disrupted. Fergawdsake, the ones on Apollo 13's Lunar Module re-entered the atmosphere at 7 miles per second, and they didn't break up, burn through, or otherwise fail.

    I suppose you could take one apart with a small nuclear device, but then that'd sort of render the whole argument moot, wouldn't it?

    The widely-quoted "statistic" that the contents of one RTG fuel capsule would give cancer to 2 billion people is misleading at best. It's like attributing the same danger to the sun: yeah, if everyone in the world goes outside and spends all day in the sun, every day, the accumulated sunburn might do that... but you know that would never happen. Similarly, there's no way a launch accident will produce the conversion conditions and dispersal mechanism to deliver the appropriate dose of RTG fuel to the world's population. Not even if the accident disrupted the capsule (which is highly unlikely in itself).

    There's no legitimate concern; it's just fear of the nuclear boogieman.

    ---

  • But your telescope does not collect cosmic dust [mpi-hd.mpg.de], or does it ?
  • Yeah, it's probably just a Death Star waiting to pick up George Lucas and then blow earth to bits.


    --
    Chief Frog Inspector
  • Not to be too picky, but White Star Lines is planning to build a new Titanic. See this link [put.com] for more info. And they expect to have it ready by 2002 for the 90th anniversary. $500 million doesn't even seem that expensive. Isn't that what a B2 goes for on Ebay? There are also 4 other projects going on to build replicas.

    Now, if we can only get Leonardo DiCaprio on board... Oh, wait, he could just float around on Kate Winslet.
  • It's a 24" Techtron, not just a tasco, and yes that was supposed to be humorous.
  • Just to clairify:

    The "surface" that is seen is just gas.

    There is a liquid He core.

    Before Jupiter were big enough to have solid He it would start fusing and become a sun.

    I just wanted to say there is no surface to land on because you would fall to the center and be crushed :)

  • I do realize that there is a tremendous amount of data that NASA missions collect and their relavence. I fully support NASA and wish that Congress would give them adequate funding.
  • by Shimmer ( 3036 )

    Talk about nitpicky. Next you'll tell us that the area of a circle isn't pi*r^2, but actually 0 because a circle is "all planar curve".

    I think it's commonly understood that the "volume of a sphere" denotes the volume of the space enclosed by the sphere.

  • by talesout ( 179672 ) on Monday October 09, 2000 @10:45AM (#720294) Homepage
    He may have been moderated as funny (and I hope that was his aim) but there are people that actually believe this kind of thing.<br><br>
    Speaking of which, why is there no moderation tag called Sad?
  • Remember, Cassini is going to Saturn.
  • I hate that code option!
  • The pressure would be to great anway. They would need to focus on 'floating' a probe at a safe level of Jupiter's atmosphere. From there they could study the core.
  • You have to wonder if mankinds collective intellect has "peaked" since the Apollo days. It strikes me that knowledge and know-how are very much a momentum issue. As we get more and more dependant on instrumentalites to create these large systems we become less able to conceive, analyze and maintain them as time goes forwards. Perhaps there is a limit to how far we will get in these endeavours without suffering large costly setbacks. There is only so much scientific reasoning you can fit in a human brain and we don't network that well.
  • "Could there be something just beneath the layer of gases like a small moon that is dense enough to cause the red spot?"

    A moon, with sufficient gravity to attract (and hold) an atmosphere would be whizzing around Jupiter so fast it would be a blur, probably losing it's atmosphere in the process. I'd expect more of a foil shape were this the case.

    The redspot is fairly symetrical and would likely be homogenious, or some representative particle or combination of sympathetic particles. Rather like taking dough and rolling it between your hands produces a cylindrical shape, which rotates representative to the difference between the velocity of the surfaces (hands).


    --
    Chief Frog Inspector
  • by Anonymous Coward
    Not saying that I agree with the protesters, but it was alot more then "a couple wacko's"

    Yeah, it was a WHOLE LOT of wackos.
  • But Jupiter is the male god of war!
  • Here are links for the:

    1/37 Scale Cassini Model [nasa.gov]

    and

    1/45 Scale Galileo Model [nasa.gov]

    I actually built the Cassini one a couple years ago, took about 20 hours or so. Had it (and a mini intel Pentium astronaut) hanging from the giant spiderweb made from network cable over my desk. That is, the SECOND attempt took about that long. I got about halfway through the first attempt before figuring out all the skills needed to do a half-decent job of it, then crumpled it up and started over again.

  • Remember NASA admits it couldn't rebuild a full Saturn V today if it wanted to.

    I'm sure i've seen estimates that it would take 10 years to put another man on the moon as the old tech can't be readily reproduced.

    I think it is fair to say that by many outsiders views mankind reached its furthest point of expansion 30 years ago and has since contracted.

    Of course you could argue that the voyager probes and that man-hole cover that was accidentally turned into the fastest man-made object in history in the first underground a-bomb test (ture story) have continued to push outward the buble of our exploration.

    And lets face it.

    Most advanced cultures probably disapear up their own fibre-optic pipes once they do the math on interstellar travel.

  • Guess what? The risk was non-zero from the moment you poked your head out of your mother's crotch.

    Either deal with it, or crawl back in your (metaphorical) cave. The rest of us have places to go and planets to see.
  • Very interesting. However, the first words in the Comments section are "Modernized,oil-fuelled." In other words, this is just a modern ship that looks like the Titanic. The insides are different, and it's the insides that are the hard part. Building the hull of a Titanic lookalike is just as easy as building the shell of a Saturn V lookalike.

    Thanks for the link, though.
  • Oh and from what I heard to colors on the probe are ALL wrong! An 11 meter boom and a lander? Oh, PLEASE! NASA! NASA! Mr. Cassini would not approve! Now had Mr. Cassini's services been retained, I'm seeing the most lovely little sun dress and a pair of matching flats.And we have just got to do something about that antenna dish. It's been done to death!

    -----------
  • What nonsense! When the Saturn-5 was launched we weren't sending up dozens of satellites per year. We weren't routinely sending supplies to manned space stations. We weren't routinely doing manned launches to repair broken satellites or correct their decaying orbits.

    There are far more "missions into space" now than ever before. This is a huge advance on 30 years ago.

    Sure, we can't build a Saturn-5 today. That's mostly a matter of supportive industries. It's the same reason the European beer brewers are having trouble getting trained hoopers. It's the same reason you can't pickup some cheap spare parts for your steam-powered ocean cruiser. It's the same reason that makes electronic valves so rare.

    In each case the technology was superceded by something better/cheaper/faster. Wood barrels replaced by aluminium kegs. Steam-powered ocean cruisers by diesel powered cruisers. Electronic valves by transistors. The old technology still exists but only for hobbiests, and occasionally for specific niche applications. It certainly makes the old technology more expensive and far less accessible.

    Not being able to build a Saturn-5 isn't a sign of decline. It's a sign that the technology behind the Saturn-5 was made redundant

  • your server isn't responding
  • Actually...
    Jupiter is male, but is not the god of war. Mars is the god of war. Jupiter was the king of gods. Also commonly known as Zeus, by his Greek name (the names that the planets have are the Roman names of gods that were Greek in origin).
  • I notice that there are a number of white "spots" below the great spot at about the latitude the Schumacher Levy 9 fragments impacted. does anyone know if these could be remenants of the impacts?

    -----------------------------
  • "The price of freedom is eternal vigilance" Colonel Blair, Wing Commander 4
  • By your same logic, it's unfair of the airlines to send planes over my house/place of work because there's a non-zero chance that one will fall from the sky killing me.

    Where are the protests?

  • Well if you want to fight totally lame, straw-man arguments so that you can feel victorious, be my guest. Just don't attribute the straw-man arguments to me. I didn't post anything about the legitimacy of non-zero arguments, so perhaps you meant to reply to another post.

    What I said was that the magnitude of a negative outcome as well as its probability is a legitimate factor in Risk Assessment. Even small children understand this.

    Imagine that Alex regularly does yard work that requires the use of a long-handled tool. This tool is stored on a high shelf and Alex knows that if he tries to get it down using only one hand, it will swing down and strike his leg about one in six times. He finds that it saves time to hold another tool while he gets the long-handled one and calculates that the occaisional slight bruise is an acceptable risk. Now imagine that Alex is invited to participate in a game of Russian roullette. Again, there is a one-sixth probability of a negative outcome. The risk however is much greater...and Alex declines to participate in the game.

    Of course, the average person is woefully ill-equiped to make an informed judgement about the risks in the Cassini mission... And many people reacted out of an unreasoned reaction to anything "nuclear".

    But not everyone raising the issue was irrational or ignorant and some scientists presented plausible, valid (in the logical sense) arguments that there was reason for concern. The fact that the probability was low and that no negative outcome occurred does not invalidate the argument. Tesserae's statement that all the arguments suggesting that Cassini posed an unacceptable risk was "not right" consisted of assertions about the low probability of negative outcome and ignored the real importance of magnitude of negative outcome in risk assessment.

  • My primary point was that you don't acknowledge that the magnitude of a negative outcome, not just its probability, is a significant factor in calculating risk.

    Not all those who raised concerns were mindless, ignorant anti-nuke zealots.

    You mention the integirty of the RTG in the Appollo 13 accident, but not the release of plutonium during the failure of SNAP 9-A in 1964. NASA's records [nasa.gov] indicate that in 22 missions with RTG power sources, there have been three accidents, one of which resulted in the release of radioactive material(NASA. Some might examine this record and draw the conclusion that NASA's methodology in determining accident probabilities is flawed. Before Challenger, the probability of catastrophic failure during shuttle launch was calculated as being very low. After the accident, the probability was recalculated and is now estimated to be much higher...

    NASA's 1995 environmental impact study [newscientist.com] indicated that a potential Cassini failure could result in 2,300 fatalities over a 50 year period. This estimate was later reduced to 120 fatalities, but the studies seemed to be an official confirmation of the negative scenarios that alarmed some people.

    I agree that the risk was worth taking, but I disagree that there was no risk.

  • My primary point was that you don't acknowledge that the magnitude of a negative outcome, not just its probability, is a significant factor in calculating risk.

    When did I not acknowledge the magnitude? The magnitude is just very small -- that was one of my original points...

    Not all those who raised concerns were mindless, ignorant anti-nuke zealots.

    You're right: not all those concerned were mindless and ignorant. Some had specific agendas. They were all anti-nuclear zealots, and they fed the fears of those less knowledgeable... and those less knowledgeable are afraid of the nuclear boogieman.

    You mention the integirty of the RTG in the Appollo 13 accident, but not the release of plutonium during the failure of SNAP 9-A in 1964. NASA's records indicate that in 22 missions with RTG power sources, there have been three accidents, one of which resulted in the release of radioactive material(NASA. Some might examine this record and draw the conclusion that NASA's methodology in determining accident probabilities is flawed.

    The SNAP 9-A RTG performed as designed: it burned up in the upper atmosphere rather than delivering its contents to the surface (BTW, your link is broken and I can't make it work either; slashcode keeps throwing in spaces and returns). There is good argument that the design philosophy was flawed, and NASA did indeed redesign the RTG fuel elements to survive reentry and contain their fuel -- which they've done in all subsequent accidents, as I said.

    For what it's worth, I clearly stated that I was talking about the Cassini RTGs -- that doesn't include the earlier (and obsolete) designs.

    Before Challenger, the probability of catastrophic failure during shuttle launch was calculated as being very low. After the accident, the probability was recalculated and is now estimated to be much higher...

    You're right -- that's why I said "they are far too conservative when estimating risk, at least since Challenger."

    I'm not arguing that NASA's perfect (geez, those who know me think exactly the opposite!). They've been overconfident in the past; they are now paranoid. It'd be nice to see them adopt the middle course.

    NASA's 1995 environmental impact study indicated that a potential Cassini failure could result in 2,300 fatalities over a 50 year period. This estimate was later reduced to 120 fatalities, but the studies seemed to be an official confirmation of the negative scenarios that alarmed some people.

    This is the sort of thing I'm talking about: NASA does a detailed study, admits there is a trivially-small (less than 10E-6) chance of a problem which might kill fewer than the number of people annually killed by lightning strikes (for example), and the anti-nuclear faction screams, "See? We were right! Our scenarios are supported by NASA's study!" -- when in fact, the ANZ's are claiming that billions of people would die. NASA's study said no such thing -- and in fact they later downrated the risk, for good reasons (their initial assumptions were too generous).

    I agree that the risk was worth taking, but I disagree that there was no risk.

    One more time: I didn't say there was no risk, I said the risk was trivially small.

    I work in the aerospace industry. Risk assessment is part of my daily life -- and in fact it affects me personally, every time I step out of an airplane with equipment I've designed on my back (I worked in the skydiving equipment industry before I got into aerospace work -- and I still use my "legacy" equipment).

    The point I'm trying to make is that there's no such thing as zero risk, no matter what you do; some risks are so small that they can be reasonably ignored, others require a tradeoff study and some should require approval of the subject population. Flight of the Cassini RTGs falls into the first category (it's orders of magnitude less than the risk of deciding to play golf and getting hit by lightning), despite the fearmongering of a few biased individuals.

    ---

  • Note to the uneducated: Jupiter has no surface, it is all clouds.
  • by Sharkey [BAMF] ( 139571 ) on Monday October 09, 2000 @10:24AM (#720317) Homepage
    Jupiter's gonna be pissed that we got it's bad side. I know from experience that she hates it when we take pics of her *spot*I tried to tell her it's distinguishing, that it gives character, like Cindy Crawford's mole, but she just sat there and expelled gasses and sulked. Bitch. Sharkey
    Bamf.com [bamf.com]
  • Have they proven the Arthur C. Clarke idea of there being a large diamond core in there?

    If you peer really closely at the red (dark grey? :-) spot in the middle, you can see forever...

    We can't see any rings in this photo though.

    /prak
    --
    We may be human, but we're still animals.
  • by snmpkid ( 93151 ) on Monday October 09, 2000 @10:25AM (#720319)
    Datalink Flaw in Titan Probe: European Space Agency engineers have discovered that there is not enough bandwidth in the link between its Huygens probe and NASA's Cassini spacecraft to handle the Doppler shift between the two as the ESA probe parachutes toward the surface of Titan, triggering an inquiry into why the shortfall wasn't discovered before NASA launched Cassini and Huygens to Saturn and how to get around it now. As it stands, ESA said, the "probe data relay subsystem" (PDRS) won't be able to recover all the data generated by Huygens' six instruments as it descends into the moon's dense atmosphere of nitrogen and methane and settles on the surface. NASA launched Cassini and Huygens together on Oct. 15, 1997. The flaw lies in the European receiver aboard Cassini that will receive data from Huygens. ESA said an end-to-end in-flight test series in February suggested there was a problem, and extensive ground testing early last month at ESA's Operations Center (ESOC) in Darmstadt, Germany, confirmed "that the existing link would not support full data recovery under the currently planned mission scenario." (Aviation Now)
  • by IvyMike ( 178408 ) on Monday October 09, 2000 @10:25AM (#720320)

    If you want to find out more about the Cassini-Huygens mission, you should check the NASA web page [nasa.gov] on the mission. (Was it just me, or was the story as posted need more info?)

    P.S. Can anybody figure out why the links on the Challenging 1/37th paper model of Cassini [nasa.gov] seem to be broken? I want to build one of these puppies!

  • Yup, that's Jupiter. Looks the same as always. What now?

  • by RJ11 ( 17321 )
    So how long before we start hurling robots to land on it? Then how many millions go down the toilet before we actually land something successfully?
  • by 64.28.67.48 ( 217783 ) on Monday October 09, 2000 @10:25AM (#720323)
    Available up a couple of levels here [nasa.gov] on the jpl site.

    -------------
  • note to FreeMath: jupiter has no 'earthlike' surface, but there is a delineation of what is jupiter and what is not. just like a theoritical sphere has no 'real' surface, but it still has a surface. and since we haven't looked too deep into jupiter, there might be solid matter in there somewhere.
  • This is all a lie. Give me a break. We all know this was formulated by the government to make us pay our taxes to fund NASA. Look at the image. Its a rubber ball skillfully painted to what we think Jupiter looks like (the text books are just tools of the government). We should lessen the spending on NASA and put it towards guns and tanks. NASA is a way to channel money into the new UN which is trying to take over our country as it is. Arise my fellow AMERICANS and fight the lies that our so called government is attempting to lull us to sleep with!

    Bingeldac denies any responsibility for the
    spelling and/or grammatical errors above.
  • Point the way oh holy one.

    I have waited for the proper time, and have realized that the call to arms I've been seeking is now!

    BTW, I saw this quote at the bottom of the page:
    When a girl marries she exchanges the attentions of many men for the inattentions of one. -- Helen Rowland

    And I just want to say that this is highly offensive to me as a happily married man.

    I mean, what the hell, if a man were to state something like, "Getting married just means you don't get any sexual attention at all" he would have every woman on the planet ready to rip his dick and balls off and eat them for lunch (and interesting idea in and of itself). Oh well, maybe it's just late in the day and slashdot and usenet have become the most frustrating possible endeavors that I am ready to commit an on-line suicide. Bye, bye karma. Bye, bye self-respect. Fuck-all moderators!
  • It's a nice picture, because of it's clean and clear shapes. People liking pictures like this should install open universe. It simulates our "sun system". And it looks pretty Nice.
  • Actually, it was more than that.

    I (and others) participated in a pro-Cassini demonstration in Washington DC. There were a good # of anti-Cassini demonstrators across the street.

    Their general opinion was "nukes are bad, m-kay" ... but they managed to get a piece on 60 minutes as well.

    I'm glad NASA faced down the protests and launched the spacecraft, and I'm happy to hopefully have participated a little bit in that success (though I'm not neive, I'm sure it would have gone off even w/o me).

    Anyway, I wear a small Cassini mission pin on my jacket that I got that day.

  • Let's consider: 1. Large corporations suck at moving quickly.

    2. Technological and scientific advancements require fast movement (mentally speaking).

    3. Exploration has hit a point where large 'corporations' (read governments) are required to pursue endeavors

    4. There is little 'percieved profit' in space

    5. No corporation (especially government politicians) want to deal with something that won't give them immediate returns (or sexual pleasure).

    So we can positively conclude that if the governments and other businesses interested in space are the 'collective intellect' of humanity, then by god yes! Our collective intellect has not only peaked, but has been on a steady decline for the past twenty to thirty years.
  • The comparison to Apollo is funny, given that three people died and three more almost died, due to design flaws.

    Face it, in any complex system and even most non-complex systems, the only way to find all the bugs is to test them out. For a three-and-a-half billion dollar probe that's as complicated as it is, it's amazing that they have as few problems as they do.

    The peak you speak of may exist (I doubt it), but we certainly haven't come close to it yet.
  • you'll be amazed... and anyway..
    What is there to loose?
  • Don't you mean "...lies which our government is attempting to lull us to sleep!"

    --
  • you could not have possibly seen it "just as nice" in your telescope. the resolution of the cassini image is taken at 500Km/pixel, you aren't coming anywhere near that with your crappy little Tasco in the back yard.
  • There were also several more articulate explanations of the dangers involved...

    Unfortunately, it takes more than just being articulate to be right. These people you link to, while articulate and even genuinely worried, don't happen to be right.

    The risk was non-zero...

    The risk was non-zero, but it was also trivially small. The biggest risk from a launch disaster involving RTGs is that one of 'em might hit you on the head as it lands (but you'd have to be in a boat off the coast during the launch, and in the launch path...).

    The RTGs carried on Cassini are designed to withstand re-entry and impact without being disrupted and spreading their contents. There have been at least two cases where a booster carrying RTG-equipped payloads blew up, and the RTGs landed on earth. In both cases (one off Florida, the other off California) the RTGs were recovered intact, refurbished, and relaunched on other mission. There was no spill, nor a danger of one. There have been no cases where a hardened RTG has leaked.

    ...NASA does not have what I would call a good track record on risk estimation.

    While I tend to agree with that, in my experience it's because they are far too conservative when estimating risk, at least since Challenger. I know that the programs I've worked on have cost more than they should, and weren't allowed to do things that were thoroughly desirable, because the risk was judged too great -- even though others have used the questioned technologies successfully.

    ---

  • You did know that the Beavers are MIT's mascot too, didn't you?

    --
  • note to the person who thinks he's not ignorant: jupiters core is made of liquid metallic hydrogen. no rocky core. its too hot.
  • "...Jupiter's Winds: Vortex Pancakes versus Taylor Columns:
    Marcus P. (and others), UC Berkeley."
    http://www.npaci.edu/enVision/v1 4.1 /marcus.html [npaci.edu]
  • So how long before we start hurling robots to land on it? Then how many millions go down the toilet before we actually land something successfully?

    Well, it depends on how you define your terms...

    First you have to be clear about what you mean by "land on it" -- Jupiter is a huge gas giant and while "we" might "hurl robots at it", the goal would be to sample its atmospheric composition and conditions, not land on it.

    Second, you have to define what you mean when you ask "how many millions must go down the toilet".. etc. If you are wondering how much money will be spent on medical care for uninsured cigarette smokers over the next few years, or how much will be spent on cosmetics or disposable, single use plastic containers or glossy porno printed matter, or fuel inefficient SUVs... then the number is probably staggeringly high.

    But if you are wondering how much money will be wasted by NASA beofre a probe is sent into Jupiter's atmosphere then the answer is: none at all. The Gallileo mission [nasa.gov] sent a probe into the Jovian atmosphere on December 7, 1995. The probe transmitted data for almost an hour and deropped about 200km into the Jovian atmosphere before rising temperatures caused it to fail.

  • I don't believe he does, but I'm just trying to lull you to sleep with this post...
  • http://www2.jpl.nasa.gov/files/images/browse/pia02 972.gif
  • If it makes it that far!

    A good friend of mine worked on that project for a while, and she told me nobody at NASA expects Cassini to complete the mission. Apparently, they had a bunch of Jews on the initial design team.

    -The Reverend (I am not a Nazi nor a Troll)
  • then again...

    You may addressing the wrong questions. I happen to agree with you that the risk was worth taking, but I also recognise that there is an ethical problem with putting people's lives at risk without their permission. The probability of an accident was low, but the potential loss of life of that hypothtical accident was high, hence the legitimate concern.

  • Can we replicate the Great Pyramid today? You bet we couldn't. Maybe with a lot of time and more money than God, but then the same holds true for the Saturn V. Could we build a V-2 today? Nope. How about a Titanic? A Fulton steamship?

    Here's a good site. I assume you know of the Me-262, the German WWII-era jet fighter. A lot of them were built, and under wartime conditions with heavy bombing from the allies. Now a company in Texas is building some replicas. It's taken them seven years to make just a handful, and they're not done yet. It's still not a perfect copy, since they're using commercially-available engines instead of the original design. The link is here [stormbirds.com].

    Does that mean that the aircraft industry has been in a decline since 1945? Of course not. That would be silly. A modern jet fighter is superior in every concievable way to the Me-262. We can't build a Saturn V. We wouldn't if we could. If we wanted to go to the moon, we'd redo it, with the benefit of thirty more years of experience in space flight, and we'd end up with something better.

    As far as our direct reach with human beings is concerned, we have pulled back since 1972. However, we now send something like fifty people a year into orbit. You can launch your own satellite into space without needing enough money to buy a medium-sized country. Our time is coming, not going. Apollo was an amazing achievement, but in the end it was basically a stunt. Soon enough we will have something more significant than just sending two people to the surface for a day.

    The math on air travel and satellites was just as horrible when those were impractical as the math on interstellar travel is now. Don't doubt the abilities of your children's children's children's children.
  • Yeah, I remember the footage of the protests outside the whitehouse. A protestor holding up a sign that said "Our last sacred space" with a depiction of an alien head as commonly viewed in popular culture (X-Files). Perhaps they forget that uranium is a product of supernovas and is scattered throughout space. As I said, wackos.

    --
  • More importantly, such a moon would be well within Jupiter's Roche Limit [uoregon.edu] and would disintegrate under the strain of tidal forces. Consider that these forces are responsible for the thrermal activity in Io's core... No way a moon could survive deep in the atmosphere.
  • OK, I pretty much agree with you but my bullshit dector went off on the following points:

    1)They were all anti-nuclear zealots.
    you are making a blanket generalization about a large population and I know that in at least two instances (friends who tried to persuade me that there was too great a risk) you are wrong. Some of the people who opposed the Cassini launch were not ANZs, as you call them. You are certainly correct that ANZs with a veneeer of scientific credibility persuaded many ignorant people into fear, but that does not make the ignorant dupes ANZs

    2)it's orders of magnitude less than the risk of deciding to play golf and getting hit by lightning
    Statistical bullshit, as I'm sure your are well aware - the chance of a golfer being hit by lightning on a perfectly clear day (no clouds in the sky no storms in the region) approaches zero - yes, it's even smaller than 10E-6... There has never been a case of a golfer being hit by lightning in perfectly clear conditions.

    3) The SNAP 9-A RTG performed as designed: it burned up in the upper atmosphere rather than delivering its contents to the surface
    The AEC detected SNAP 9-A radiation in the air and on the ground. The radiation levels were minimal but it is simply false to claim that the contents of SNAP 9-A's RTG did not reach the ground. That's why they did the redesign!

    4)...might kill fewer than the number of people annually killed by lightning strikes...
    The number of people killed in the US each year by lightning strikes is about 100. The number of fatalities in the NASA environmental impact studies was first 2,300 then 120. The second number is close to, but still higher than, the number of people killed annually by lightning... This minor factual error aside, the important distinction is that the lightning strike tally is the result of many events while the Cassini RTG scenario was for just one. Your comparisson is between categorically different causes. It's like a mass murderer claiming that his having killed 80 people isn't really such a bad crime, compared with the 15,000-20,000 people killed in DWI accidents each year, so he should get a light sentence.

    [approaches dead horse, bat in hand]
    The magnitude of the perceived threat was great, hence the higher risk assessment, despite the low probability of a negative outcome. I am persuaded that the risk was even lower by the arguments [nss.org] raised by Jeff Cuzzi, but I think it's important to recognize the legitmacy of people's concern and to assuage it through rational dialog rather than ad hominem attacks and hyperbole -- even if they are all a bunch of ANZ wackos... after all, the ANZ-influenced herds of non-cognoscenti help to influence the science budget.

  • These kind of features come and go all the time. They are storm systems.
  • yes but we can't replicate the functionality of the Saturn V.
  • Can we replicate the functionality of all your other examples?

    answer: Yes we can

    Can we replicate the functionality of the Saturn V?

    Answer: No we cannot

    Thats the difference.

  • OK, I pretty much agree with you but my bullshit dector went off on the following points:

    Let me assure you that I'm not bullshitting -- I think you're just misunderstanding me.

    You are certainly correct that ANZs with a veneeer of scientific credibility persuaded many ignorant people into fear, but that does not make the ignorant dupes ANZs

    Ummmm... the ones "with a veneer of scientific credibility" are the ones I was calling ANZs; the dupes were the ones I said were afraid of the nuclear boogieman. :)

    Not knowing your friends, I can't pass individual judgment; however, I've met no one who understands the subject matter and who isn't an ANZ, who opposed the launch. Some were even willing to admit privately that they deliberately inflated the disaster scenario, but they regarded it as important enough an arena that they were willing to do that. It's called politics, and it's not science.

    2)it's orders of magnitude less than the risk of deciding to play golf and getting hit by lightning
    Statistical bullshit, as I'm sure your are well aware - the chance of a golfer being hit by lightning on a perfectly clear day [snip]

    You're changing the universe of discourse: the majority of the lightning-strike victims each year are indeed golfers, which demonstrates that some do decide to play golf in less-than-ideal conditions. This is as factual as the NASA environmental impact study.

    The AEC detected SNAP 9-A radiation in the air and on the ground. The radiation levels were minimal but it is simply false to claim that the contents of SNAP 9-A's RTG did not reach the ground. That's why they did the redesign!

    It's a fact that SNAP 9-A burned up in the upper atmosphere; it's the atmosphere which delivered some of the radioactive results to the ground. My statement was that the fuel elements didn't survive to impact the ground. Aside from that, you're right: that's why they did the redesign... I actually said that, I thought!

    4)...might kill fewer than the number of people annually killed by lightning strikes...
    The number of people killed in the US each year by lightning strikes is about 100. The number of fatalities in the NASA environmental impact studies was first 2,300 then 120.

    The NASA worst-case estimates were spread over 50 years following the presumed accident; that's 46/year in the first case, 2.4/year in the second... both of which are less than 100/year, the second by two orders of magnitude. (I carefully chose that example so I could say "orders of magnitude...")

    ...the important distinction is that the lightning strike tally is the result of many events while the Cassini RTG scenario was for just one.

    The Cassini worst-case scenario was the end result of many different events going wrong -- not a single event. If it would make you feel better, I'll substitute "flying on a commercial airliner" for "playing golf." The statement still stands, for the population of the planet.

    That aside, my point was that people daily decide to take risks which are much more significant than the worst-case Cassini RTG accident; they do it without thinking about it, because they perceive the risk as minimal. The concern about Cassini was manufactured by a small group of people, and was blown way out of proportion by the media.

    Your "mass murderer" analogy's just a straw man argument.

    The magnitude of the perceived threat was great, hence the higher risk assessment, despite the low probability of a negative outcome.

    This is a critical point: the "perceived" threat wasn't realistic -- it was a manufactured media manipulation. The actual threat was low, as I keep stating... that's been my whole point!

    I think it's important to recognize the legitmacy of people's concern and to assuage it through rational dialog rather than ad hominem attacks and hyperbole -- even if they are all a bunch of ANZ wackos... after all, the ANZ-influenced herds of non-cognoscenti help to influence the science budget.

    Oh, I do recognize the legitimacy of people's concerns, and I argue differently with them in person than I do with you on /. I'm generally a patient sort of guy -- but this must be the fifth or sixth RTG topic that I've met the false arguments on, and this time I was pretty tired of it.

    Part of what makes it especially poignant is that I worked on Pathfinder, which was very nearly a waste of effort because the mission was deliberately crippled by choosing solar rather than RTG energy sources; if NASA had used RTGs, the lander would almost certainly still be operating, and the rover might well be. Instead, the whole thing was over in a couple of months. That's sad. By spreading the costs over a much longer mission, they could truly do faster, better, and cheaper.

    Despite all that, my arguments weren't hyperbolic -- Jeff Cuzzi gave even more trivial risk levels, such as stating that the Cassini risk per individual was six orders of magnitude lower than that of driving a car one mile. And I certainly didn't intend to advance ad hominem arguments against the innocent dupes of the ANZs -- but I did intend to slam those who deliberately manufactured false arguments against the project.

    I suspect you're right, in that you and I mostly agree; you were just unfortunate enough to be in the wrong post at the wrong time... :) [dead horse gets up and nonchalantly ambles away...]

    ---

  • The Saturn V design is in the class known as Big Dumb. Were we to launch a moon mission today, we'd probably send up a lander in one rocket, the living module in another, supplies in a third, and crew in a fourth. Get them all to the space station of your choice, launch the mission from there. Granted, Big Dumb is a very good way of engineering things sometimes, but as techniques get better it's not usually needed.

    Total costs for the development of the Saturn V were $9.3 billion [nasa.gov]. Apparently in 1960s dollars, too. The total program cost $25.4 billion (same link), or about $95 billion in today's dollars.

    I would be surprised if a smart team, using off-the-shelf components entirely (ok, maybe a lunar lander would have to be made from scratch) would cost more than, huge overestimate here, $5 billion from start to finish. If the Russians can keep a space station manned and supplied year-round for something like $200 million, I'm sure we could do a moon mission for less than $5 billion. Then why don't we? Because we don't want to. Not because we can't.
  • I don't know what would be more sad, if you were trying to be funny with this post or if you were actually serious.
  • A 1-in-a-million risk of 120 people dying over 50 years? So a 1-in-2,500,000,000,000,000 increase in the chance of any one individual dying in each of the next 50 years. Sounds like "no risk" to me.
  • I've seen it just as nice, in colour, in my own telescope, without paying $92M

    Still a pretty awesome site, I must say. I mean, yeah, nobody (including me) would be much impressed with that picture, especially for the money. And yes, color might've been nice... but I have to say that it's interesting to finally see a photo of jupiter where the "Big Red Spot" isn't in the upper right hand corner... a nice little reminder that in space, there are no compass points.

    Whenever I look at images of planetary bodies, I'm once again awestruck by the incredible vastness of our universe, and my own insignificant actions as a part of it.


    -The Reverend (I am not a Nazi nor a Troll)
  • by clinko ( 232501 ) on Monday October 09, 2000 @10:29AM (#720355) Journal
    I hate to be a karma whore, but here's a link to information on cassini
    Cassini info [nasa.gov]
  • well actually the pressure within such a massive gas ball ensure that there will be a solid at the core. I dunno about diamond as Clarke thinks, but metallic Hydrogen always sounded pretty reasonable. In fact, I remember seeing an article or two about it. However, where it goes from gas to solid (any liguid in between? I doubt it) might not be so well defined. the pressure would dramatically increase as you approached the center, then it would become extremely dense and it would be very difficult to move through it, and below the point where you have almost no mobility I'm sure you would say is solid. But right on the surface there it's pretty thich too!
  • Note to the ignorant: Jupiter is made up of heavy gases with a dense rock core at the center.
  • Ammonia ice particles are white
    I had actually thought the white was from all the socks that were lost throughout the years, and that the red was from all the uniform tunics of those poor landing party guys in Star Trek.

    Next they will say that Santa is really a out of work Elvis impersonator tyring to find his next wedding gig.

  • Like the mixed-success Jupiter Galileo probe,
    Casini's attenna appear to be on the blink.
    Thta means NASA will have to narrow scope.
    NASA folk are pretty creative. They achieved most of Galileo's objectives using the 100 times
    slower backup attenna. They did it with data compression algorithms that had advanced considerable the decade Galileo was in journey.

  • Note to Mike Bridge:

    The idea of "landing" connotates a solid surface, which Jupiter lacks. Also a theoretical sphere, as typified by x^2+y^2+z^2=r^2, in fact does not have volume (though it encloses volume) it is all surface.

  • I am wondering when we get to find out about the information that Cassini collected. The purpose of the close encounter with Jupiter was 2 fold--to get momentum in order to slingshot to saturn (its next stop) and to collect information about Jupiter and its magnetic sphere around it (and how the solar winds effect this).

    We have found that the solar wind changes as it moves through and near Jupiters magnetic sphere, and this is the first chance we have really had to find more information about this.

    So again I say: The pic is good but I want more. BTW: More information about this Cassini/Jupiter project can be found at http://www.spaceflightnow.com/news/n0006/20galileo cassini/

    Just to find out about where Cassini has headed and been check out http://www.jpl.nasa.gov/cassini/MoreInfo/faq.html.
  • that's the plan come mid december i think. right now, Cassini is about 50 Million Miles from Jupiter, that's nowhere near Jupiters magnetosphere/bow shock. In it's orbit Galileo just left the magnetosphere around jupiter (this past July) for the first time since it arrived in 1996. It was somewhere around 15 Mil. Miles when it did so. The particle/plasma science expiraments will probably be switched on to gather data when Cassini gets closer to the boundary between Jupiters magnetic field and the solar wind.
  • I probably do but thats why I have a disclaimer. To many servers = not enough time to proof read. Thanks for the help.

    Bingeldac denies any responsibility for the
    spelling and/or grammatical errors above.
  • by Derek Pomery ( 2028 ) on Monday October 09, 2000 @11:36AM (#720364)
    It's energy esource?
    http://www.ametsoc.org/AMS/newsltr/nl_03_00.html [ametsoc.org]
    I've been trying to dig up an article I read about how something like this was caused to form naturally. No luck so far, but I suspect it may have been this researcher's project.
    http://www.coaps.fsu.edu/~meyers/fig/vortex.html [fsu.edu]
  • Just underneath the Great Red Spot are three white spots in a line. Does anyone know, are these storm systems or are they leftover from the Shoemaker-Levy 9 cometary impact?

  • by Anonymous Coward
    If you'll pluck your shrunken head out of your tiny teeny little backwater hole, you'll remember that the controversy involved much more then "a couple wacko's from Greenpeace". There were large protests in New York, Baltimore, San Francisco, London, Paris; many NGO's were involved, including Greenpeace, the national Green Party, Rain Forest Action Network, among others. There were spots on 60 minutes, front page news in the New York times, a bill in congress.

    Michio Kaku (Who among other things, co-created String Theory) was pretty critical of the Cassini mission. Here's his analysis [americanreview.net].

    Not saying that I agree with the protesters, but it was alot more then "a couple wacko's"
  • While the details of why the Red Spot exhibits such stability are still unknown, let me try and paint an explanation in broad strokes.

    First off, Jupiter (at least it's outer atmosphere, presumably the whole thing) rotates very quickly, which leads to both a nasty coriolis force and significant velocity differentials in the middle-latitudes. Thus, cyclonic activity is favored.

    Moreover, the Red Spot actually behaves a great deal like a terrestrial hurricane, except that it's always over warm water (not water, really, but the same convective processes occur) since there is no "land" and a considerable amount of heat flowing from the interior. Infrared pictures, as it happens, do show the Spot as a intense radiator.

    Both computer models and observations suggest that this combination of factors in conducive to stable cyclones that will tend to swallow up smaller ones.

  • But then why does the red spot persist? We've known about it for a couple of centuries, so if it were simply a local disruption from stability, it would have corrected itself by now, but everytime we look at it, it's about the same shape, size, color, and relative placement on the planet. Could there be something just beneath the layer of gases like a small moon that is dense enough to cause the red spot?

    LADY MACBETH Out, damned spot! out, I say!

    I think it's probably conical, like a tornado. Due to the viscosity of that gas and the attraction to like gas particles/repulsion by unlike gas particles, due to density or some other property. Worth pondering over milk and cookies and a quick review of Oliver Wendell Jones astronomy exploits.

    Another thought, the earth's moon, which is a considerable disruptive force to the surface of the planet, has no jovian equal.


    --
    Chief Frog Inspector
  • by Ch3t ( 241022 ) on Monday October 09, 2000 @10:40AM (#720369)

    I recall there was a lot of controversy about the Cassini probe, prior to its launch. Most of this concerned its fuel, which I think was plutonium.

    The funniest thing I heard about the controversy was when some idiot in the fashion industry called the JPL to complain about using the designer, Cassini's name without permission. The idiot was politely informed the spacecraft was named after a 15th. century astronomer and not the sycophant's boss.

  • Remember, this is just the FIRST test image from the probe and no way near a final product. The probe is still 50million miles away.
  • by Barbarian ( 9467 )
    If you READ the damn articles on it, they're using the snapshots to test the imaging equipment. That is all.

    --
  • i never mentioned landing or volume, simply commented on 'surface' and 'earth like surface'

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