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Voyager 2 Detects Peculiar Solar System Edge 272

Posted by ScuttleMonkey
from the magnet-on-a-really-long-string dept.
ClickOnThis writes "CNN reports that Voyager 2 has detected evidence of the magnetic edge of the solar system (aka the heliopause) at 76 AU (1 AU = 93 million miles), much closer to the Sun than the location of 85 AU found by Voyager 1. From the article: 'This implies that the heliosphere, a spherical bubble of charged low-energy particles created by our Sun's solar wind, is irregularly shaped, bulging in the northern hemisphere and pressed inward in the south. [...] The researchers think that the heliosphere's asymmetry might be due to a weak interstellar magnetic field pressing inward on the southern hemisphere.'"
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Voyager 2 Detects Peculiar Solar System Edge

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  • I knew it (Score:5, Funny)

    by sidfaiwu (901221) on Wednesday May 24, 2006 @01:19PM (#15395513)
    I have been living in a bubble all my life.
  • Variable size? (Score:5, Insightful)

    by topher1kenobe (2041) on Wednesday May 24, 2006 @01:21PM (#15395529) Homepage
    Could it not simply mean that it changes in size? I'd be surprised if it *didn't* change in size, based on all the variable energy in the solar system. The sun changes, the planets change place, etc.
    • Re:Variable size? (Score:3, Insightful)

      by Anonymous Coward
      Yeah, but if you think about how much it would have to change in size between the two Voyager probes encoutering them.. The difference is multiple trips from here to the Sun, in not that long a time period.

      What I'm trying to say here: If it's moving, it's doing so with some gusto, at least in planetary terms.
    • Re:Variable size? (Score:4, Insightful)

      by Nos. (179609) <andrew@@@thekerrs...ca> on Wednesday May 24, 2006 @01:26PM (#15395569) Homepage
      I wouldn't think the positioning of the planets would have much to do with it. Thing of a spec of dust in front of a spotlight... pretty tough to notice the effects a significant distance away. However, given sun spots, solar flares, etc. I wouldn't think that the distance would be constant. Though a variation of around 11% is pretty significant. Of course, two data points at different times in different areas is hardly enough to make any kind of conclusions.
      • Of course, two data points at different times in different areas is hardly enough to make any kind of conclusions.

        We'll have a better picture when the Voyager 1308 readings get to us. Stay tuned !
    • Re:Variable size? (Score:5, Informative)

      by MindStalker (22827) <mindstalker@gmai[ ]om ['l.c' in gap]> on Wednesday May 24, 2006 @01:27PM (#15395575) Journal
      I believe from the Voyager I expedition that Voyager I detected and eventually cross the heliosphere where it was detected a year later. So the idea that the size stayed steady during the time then quickly switched sizes as Voyager II approached is unlikly... Unless the excape of Voyager I has upset the Gods... Then we are all doomed!
    • I also wondered if it could be changing. But if it is, I very much doubt anything inside the solar system has any measurable effect on it other than the sun.
    • Re:Variable size? (Score:5, Insightful)

      by sidfaiwu (901221) on Wednesday May 24, 2006 @01:29PM (#15395608)
      Could it not be both changing sizes and be irregularly shaped and off center?
      • Re:Variable size? (Score:3, Informative)

        by Nos. (179609)
        Hmmm, irregular and off-center. If the sun is moving at a given speed, the overall shape of the heliosphere would appear warped and off center... probably egg shaped. That might explain the difference.
        • Re:Variable size? (Score:3, Insightful)

          by MightyMartian (840721)
          This may be an incredibly stupid question, but is there any reason that we should assume that interstellar charged particles wouldn't be more powerful in one direction than another?
          • I dunno, tho I'd assume you need a hellacious volume of particules to exert this kind of pressure, and the source would consequently need to be really big, or really close... enough so that we should have seen it already.

            Of course, I'm pulling that straight out my ass.
            • ...the source would consequently need to be really big, or really close... enough so that we should have seen it already.

              The source?

              If it's daytime: go outside and look up.

              If it's night time: wait until daytime and see above.
      • Re:Variable size? (Score:5, Insightful)

        by liquidpele (663430) on Wednesday May 24, 2006 @01:47PM (#15395778) Journal
        I was more thinking it would be shaped like a commet's tail, since the solar system is itself moving, could the "bubble" actually be like a ball with a tail fading away?
        • The solar system is moving? Relative to what? Paging Dr. Einstein...
          • Ahem...I seriously thought I'd never have to explain this one on slashdot. It turns out that beyond our solar system, there is a vast amount of space and bodies that provide references against which to measure the motion of the solar system. We call that the "universe."

            For further background on this concept, you may be interested to read about galaxies [seds.org] or Copernicus [wikipedia.org].
        • Re:Variable size? (Score:3, Informative)

          by Twanfox (185252)
          The only reason comets have tails is because there is an outward pressure that forces ejected particles away from their source. Likely, the biggest way that such a 'tail' would form in the heliopause is if there was an external force pushing on it.

          Think: Earth's magnetic field.

          The magnetic field of the earth is shaped very much like a comet, but it is always pointed away from the sun and ripples as solar output changes. There is a website that seeks to model the fluxuations of the magnetic field, but I forg
    • by JebusIsLord (566856) on Wednesday May 24, 2006 @01:33PM (#15395650) Homepage
      You mean it shrinks??

            -Elaine
    • Re:Variable size? (Score:3, Insightful)

      by ClickOnThis (137803)
      Could it not simply mean that it changes in size? I'd be surprised if it *didn't* change in size, based on all the variable energy in the solar system. The sun changes, the planets change place, etc.

      Excellent point. Whether something changes spatially or temporally is a difficult thing to determine when you're measuring things from just a few spacecraft. My guess is the feature is spatial, because the two Voyagers encountered it within such a relatively short time period. However, if it is temporal (i.e.
    • Re:Variable size? (Score:5, Interesting)

      by Bob3141592 (225638) on Wednesday May 24, 2006 @01:47PM (#15395781) Homepage
      Could it not simply mean that it changes in size? I'd be surprised if it *didn't* change in size, based on all the variable energy in the solar system. The sun changes, the planets change place, etc.

      What variability? The sun is pretty constant on short time scales. The sun is being observed in detail by other spacecraft specifically designed for that task, like Helios. These spacecraft directly measure the solar wind and track the effects of solar. I'm sure the people at NASA have included that data into their analysis. They are rocket scientists, after all. The planets exert essentially zero influence over the heliosphere. So it's not like they have no idea about what's going without the Voyager data.
    • Re:Variable size? (Score:4, Insightful)

      by VWJedi (972839) on Wednesday May 24, 2006 @01:49PM (#15395796)

      "...based on all the variable energy in the solar system."

      What about the energy outside the solar system? Although the distance is much greater between the sun and neighboring stars, those stars do have a gravitational effect on the movement of the sun, the planets, and all other objects in the solar system. They probably have an electro-magnetic effect as well.

    • Re:Variable size? (Score:3, Insightful)

      by Surt (22457)
      If solar energy output varied by more than 10% in a couple of years, we'd likely have weather and temperature issues here on earth as a result.

      And the width of planets are insignificant compared to the radius of orbit, so unless the spacecraft happened to hit a one in a million chance of wandering through right on the orbital plane of one of the planets, just in sync with the orbit of that planet, this isn't a very likely explanation either.
    • Re:Variable size? (Score:3, Informative)

      by barawn (25691)
      Could it not simply mean that it changes in size? I'd be surprised if it *didn't* change in size, based on all the variable energy in the solar system. The sun changes, the planets change place, etc.

      That's actually very likely taken into account. When Voyager 1 found the heliopause, they were pretty sure that the termination shock was moving inward fairly rapidly due to it being past solar max, and so Voyager 2 would catch it pretty soon. This sounds like it happened quicker than their predictions expected.
    • Let me guess, Its shrinking due to Global Warming.
  • Er. Wait. (Score:5, Insightful)

    by Roody Blashes (975889) on Wednesday May 24, 2006 @01:22PM (#15395535) Homepage Journal
    That's two data points, and "bulging" implies a highly irregular shape, or at least an even shape that couldn't be accurately modeled by two data points.

    Wouldn't it be equally as logical to say that it's just expanding/contracting? How can they know with only two points?
    • not two points, data is being taken along two different curves over years; and if there is expansion we might just detect it
    • Re:Er. Wait. (Score:5, Interesting)

      by rockhome (97505) on Wednesday May 24, 2006 @01:35PM (#15395668) Journal
      The 2 data points aren't informing the size or shape, but are observations related to a theory.

      The theoretical belief is that it should be relatively uniform, but it does not appear to be. Are 2 observations sufficient? No, but a difference in 9 AU in the 2 observations is significant in that it is far off the scall were it less than 1, or maybe only slightly different, that would better confirm the theory. If the physics say that it ought to be uniform, and observations shows that it isn't, th theory needs to be adjusted.
      • Wow, a completely untested theory proposed when we had no data points to even base it on is invalidated by two units of data. I'm sure Rutherford would be surprised.

        Seriously, when you make a theory with no actual data, it sounds a lot like an educated guess. I'm not saying it shouldn't be done, but you'd be a fool to be surprised it was wrong or incomplete. It's a starting point, not a destination.
        • We did have data to base the theory on. The data is the known emmissions from the sun, compared to the expected emissions from other suns and such. Based on that, they were probably pretty confident of their models of what the termination shock should look like (the very fact that they can identify it suggests the model can't be too far off). You're right, though, that it's only a starting point. This observation sounds like very good justification for continuing to fund the Voyager program. NASA had been c
    • Re:Er. Wait. (Score:3, Informative)

      by ClickOnThis (137803)

      That's two data points, and "bulging" implies a highly irregular shape, or at least an even shape that couldn't be accurately modeled by two data points.

      Wouldn't it be equally as logical to say that it's just expanding/contracting? How can they know with only two points?

      Actually there is more information available than just two data points. There is the a priori knowledge of how magnetic fields and plasmas behave, the cumulative measurements of the two Voyager probes up to now along their trajectories, the

    • Re:Er. Wait. (Score:4, Informative)

      by argStyopa (232550) on Wednesday May 24, 2006 @02:02PM (#15395906) Journal
      Yup.
      Someone once explained the heliopause neatly by pointing to the splash-disk of water in a sink, with the tap turned on full. The water coming from the tap pushes out, while the water already in the sink is trying to return to the middle to go down the drain.

      Hence, you get a 'circle' where the energy of the tap water (coming out from the center) = the energy of the material trying to fall back into the center. The circle isn't perfect; it moves as the tap outpouring is not uniform and varies quite a bit.

      It's actually a pretty good analogy, since the topagraphy of the sink (as a parallel to the gravity environment) also affects that 'circle' significantly.

      Much like that, I suspect that the heliopause is hardly static; it probably bulges and deflates dynamically with solar activity (once that reaches the periphery, of course).
    • This is a great excuse to launch a few thousand starwisps outbound.
  • by Tibor the Hun (143056) on Wednesday May 24, 2006 @01:22PM (#15395539)
    ...but all that mumbo-jumbo about weak this and that seems really complicated.

    Couldn't the inward bulge on the south be because the turtle shell is pushing in on it?
  • garbage! (Score:2, Insightful)

    by Quasar1999 (520073)
    I'm sorry, I'm not a scientist and perhaps that's why I can't graps how the hell they came to this genius conclusion.

    Let's sample a sphere at two pinpoint locations, and make all sorts of conclusions on the shape of an entire hemisphere of it...??? It rained today, and it was sunny yesterday, so that means that there's a 50% chance of it raining? Insufficient data...
    • Re:garbage! (Score:5, Informative)

      by rubycodez (864176) on Wednesday May 24, 2006 @01:29PM (#15395607)
      no, we've been taking data over many years along two different parabolic trajectories, that's a HUGE difference from sampling at two little data points. And we'll keep taking data along these curves; expansion or contraction and other variations could possibly be detected
    • Re:garbage! (Score:5, Insightful)

      by misanthrope101 (253915) on Wednesday May 24, 2006 @03:05PM (#15396433)
      I'm sorry, I'm not a scientist and perhaps that's why I can't graps how the hell they came to this genius conclusion.
      Yes, your assessment of your own abilities is more accurate than your assessment of the science involved in what they are doing. What I don't see is how you started out so well, acknowledging the fact that you didn't know what you were talking about, and then stumbled on anyway to decide that they were making it all up and it was actually, as you called it, "garbage." It's as if you don't think that your own admitted, acknowledged ignorance diminishes the validity of your analysis. Are you really that arrogant? And if you are, might you not want to re-think something in your intellectual approach to science, and in fact to rational thought? Just an idea.

      No, I'm not calling you stupid. I don't understand quantum mechanics, among other subjects. However, I realize that my ignorance means that I am extremely unqualified to dismiss any article on quantum mechanics as "garbage." That doesn't mean that I have to believe everything, or that I am suffering from the "argument from authority" fallacy, only that I recognize that science has been a very productive, very successful mental process, and the bare fact that I don't understand something scientists are saying doesn't mean that they're making it all up. Just saying "Zeuss did it" is just making it up, but flying a freaking spaceship out to the edge of the solar system to gather data to analyze proves that the thought process is based on something rational and dependable, even if I don't understand all the aspects of the science.

      I know my response is disproportionate to your original post. The reason I wrote it is that too many people, knowing full well that they don't know what they're talking about, still feel eminently qualified to have a passionate opinion on scientific subjects. Usually their assessment is that the science is "garbage," that scientists are "just making it all up," and that it's just a "secular religion" used to explain away God, or some such crap. Meanwhile I'm sitting in an air-conditioned room, wearing glasses, looking at my car keys, and otherwise surrounded by things that were all created by science, none of which were created by prayer or chanting. Hearing people denigrate the scientific method, even while being surrounded by the fruits of that method, is starting to chafe my hide.

    • Insufficient data...

      Yes, you---a slashdot armchair physicist---have disassembled and shamed the work of a team of NASA scientists with three poorly punctuated semi-sentences.

      Let that be a lesson to the rest of you would-be geniuses out there using your "science" and "math" to "prove facts". Quasar1999 stands at the ready to quip your supposedly careful research into shamed oblivion. ;-)

      Tom Caudron
      http://tom.digitalelite.com/ [digitalelite.com]
    • Re:garbage! (Score:3, Informative)

      I'm sorry, I'm not a scientist and perhaps that's why I can't graps how the hell they came to this genius conclusion.

      Let's sample a sphere at two pinpoint locations, and make all sorts of conclusions on the shape of an entire hemisphere of it...??? It rained today, and it was sunny yesterday, so that means that there's a 50% chance of it raining? Insufficient data...

      You expect the termination shock to be symmetric, with the Sun at the centre. There will be interstellar influences, but the Voyagers are

  • ...it's due to the Sun's motion through the galaxy, perhaps extrasolar winds which remain undetected, or the bubble is variable like the solar wind itself, or maybe even gravitational tides due to the orbiting planets are influencing its shape. While I'm impressed that both Voyagers (and Pioneers for that matter) are still out there sending back this kind of data, there's so little to go on that a lot of rank speculation is required. Perhaps a series of probes need to be sent out to the region of the Kuiper
    • Re:Or perhaps... (Score:3, Interesting)

      by Farmer Tim (530755)
      ...it's due to the Sun's motion through the galaxy

      Unless the compression of the heliopause is on the leading edge relative to the sun's motion through the galaxy, this can be safely ruled out. This would also imply some hitherto undetected galactic medium causing a braking effect; surely any non-magnetic influence would affect solid matter as well, and cause the galaxy's rotation to slow over time (unless the medium rotates with the galaxy, in which case the motion of the medium relative to the sun is zero
  • by Glacial Wanderer (962045) on Wednesday May 24, 2006 @01:25PM (#15395562) Homepage
    Or it means that the heliopause is collapsing at an alarming rate. In other words, the sky is falling! End of the solar system! Run for your lives!
    • 'lax man. I'm pretty sure we can just reverse the polarity of the deflector beam, point it south by south and drive in reverse at warp 2.
      • Actually, I think that would override the Varion phase subsystem and result in a dangerous multiphasic plasma leak. Remember when we tried that on the Trilobites of Gleberaux V? Lieutenant McShane spent weeks resurfacing the intermediary manifolds after that misadventure, and complained about it in the Forward Lounge every night for months!

        I think if we draw off about 10% of our reserve holodeck power and re-route it to the rear sensor array, the resulting harmonics would induce a tachyon burst in all direc
    • Undoubtable creationist will claim this as yet another piece of convincing evidence of a young universe and the scientist just don't want to admit it.
      • But God must have created the heliosphere. Otherwise we might have to use lots of difficult mathematics to explain its asymmetry and how annoying would that be?

        Also, Occams razor PROVES it, because its much easier to imagine some guy coming along and just plonking the heliosphere there rather than an uncountable number of magnetic particles/waves interacting with one another over billions of years.

      • by Anonymous Coward
        Undoubtable liberals will claim this as yet another piece of convincing evidence of solar warming due to the Bush administration's non-competitive granting of projects to the Halliburton corp.
    • Your Blogger profile says you're in engineering. Have you considered a career in journalism?
    • All we need to do is wait for it to collapse a little further and then Chuck Norris can it it with a roundhouse kick and everything will be back to normal.
  • I think we need a few more probes than 2 in order to determine what the shape is. We poke 2 holes in outer space, and because one hits sooner, we are already swapping out one static shape for another... what if it just changes shape all over the place (albeit slightly)? Granted, it's not high on the priority list, but the caveat that we'd need a bunch more probes to determine a rough shape from first contact radio information.
    • Here's the thing, we have been monitoring Voyager 1 and 2 since they left Earth. So really there are a LOT more than 2 points of data, it's actually 2 continuous arcs through space. Sure, 200 more probes would provide a much nicer data set, but funding that (then having to wait 30 years) just isn't sexy.
  • by Anonymous Coward
    the question: What does God need with a starship?
  • by fernandoh26 (963204) on Wednesday May 24, 2006 @01:30PM (#15395617) Homepage
    How much you guys wanna bet some people will either:

    A) Say that this is causing global warming
    B) Say that this is being caused by global warming
  • by Anonymous Coward on Wednesday May 24, 2006 @01:33PM (#15395658)
    "computer, what is the nature of the universe?"

    The universe is a spheroid region - 705 meters in diameter...
  • Good Engineering (Score:4, Insightful)

    by Screwy1138 (976897) on Wednesday May 24, 2006 @01:35PM (#15395667)
    It's a credit to the teams that these things are still running. I feel like there is an old and new NASA. Imagine a project today to explore the edges of the Solar System (I know Voyagers did more than that but we have to keep it simple today). "Okay boys, now, we don't care what direction you go in, but could you please just not hit anything?" All in all, I really feel for NASA.
  • Symmetrical? (Score:4, Insightful)

    by mhore (582354) on Wednesday May 24, 2006 @01:43PM (#15395746)
    I read this a day or two ago, and wondered to myself, "Whoever said that it had to be symmetrical?"

    If you look at many structures in the universe, there are quite a few that are not spherically symmetrical. So either, we're in an asymmetrical blob, or there's just a more complex symmetry present. This should come as no surprise to the astronomy community, IMHO.

    It is interesting, I think. It may give insight into our local neighbourhood.

    Mike.

    • by p3d0 (42270) *
      Nobody said it had to be symmetrical, but these are smart folks who understand such things as magnetic fields and plasma dynamics, and I presume their theories told them it should be symmetrical. The fact that it's not will lead them to refine their models.

      I don't even know why I have to say this. It's scientific method 101.

  • Well, this particular carbon-unit infesting the third planet is NOT impressed.
  • by Bob3141592 (225638) on Wednesday May 24, 2006 @01:52PM (#15395819) Homepage
    I've been to the heliopause and all I got was this lousy t-shirt!
  • by mikeeg555 (976902) on Wednesday May 24, 2006 @02:04PM (#15395925)
    En1arge your heli0sphere! With our proven program, you can make your heliosphere larger and thicker in just a few short weeks. Would you like to see results by the end of the first week?... You will... Follow our program, and within just a couple months you can be 9 or more AU larger than when you first started.
  • This implies that the heliosphere, a spherical bubble of charged low-energy particles created by our Sun's solar wind, is irregularly shaped, bulging in the northern hemisphere and pressed inward in the south

    Or maybe it is a regularly shaped sphere but our sun is not the center? Maybe the center is some other extremely dense object, like 's head?
    • Always preview your posts!

      Or maybe it is a regularly shaped sphere but our sun is not the center? Maybe the center is some other extremely dense object, like {insert your favorite whipping person here} 's head?
      • Here, let me help you
        Or maybe it is a regularly shaped sphere but our sun is not the center? Maybe the center is some other extremely dense object, like fnord's head?
  • Voyager has also just realized why its credit cards don't swipe any more, and why all its Journey tapes have been erased.
  • OMG! The heliopause is shrinking! The heliopause is shrinking!
  • Hey, come on, didn't the lady say "it's turtles all the way down!"?
  • A better article... (Score:4, Informative)

    by Anonymous Coward on Wednesday May 24, 2006 @02:34PM (#15396175)
    ...from a far less clueless source [newscientistspace.com].

    Here [newscientistspace.com] is an illustration of the phenomenon.

    -mcgrew
  • This implies that the heliosphere, a spherical bubble of charged low-energy particles created by our Sun's solar wind, is irregularly shaped, bulging in the northern hemisphere and pressed inward in the south.

    I guess we need to change the name of the heliosphere to helioelipsoid or maybe helioblob.

  • Algore tried to warn us about this.
  • by jnik (1733) on Wednesday May 24, 2006 @03:25PM (#15396623)
    I should learn to not read slashdot during AGU.

    I forgot whose talk I heard yesterday (they changed the speaking order; session was SH22A) but basically: V1 passed the termination shock (NOT the heliopause; summary is wrong) at the end of 2004; this was the big announcement at last spring AGU meeting. Before that, they were seeing foreshock signatures (plasma and magnetic). V2 is now seeing those signatures, but seeing them a fair bit closer in than V1 was observing them. So, V2 has not passed the heliopause, nor even the termination shock, but appears to be nearing the TS closer to the Sun than V1 did. This is a surprising/interesting result, but not huge overturning of theory or anything. Learning the structure of the outer regions of the Solar System is the whole point of these exercises (and the upcoming IBEX mission).

  • Have you ever seen a PERFECTLY spheroidal meatball?

    I didn't think so. [venganza.org]

"No, no, I don't mind being called the smartest man in the world. I just wish it wasn't this one." -- Adrian Veidt/Ozymandias, WATCHMEN

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