Follow Slashdot stories on Twitter

 



Forgot your password?
typodupeerror
×
Space NASA Science

Voyager 2 Shows Solar System Is "Dented" 173

Selikoff writes "NASA's Voyager 2 spacecraft has found that our solar system is not round but is 'dented' by the local interstellar magnetic field, space experts said on Monday. The data were gathered by the craft on its 30-year journey when it crossed into a region called the 'termination shock.' The data showed that the southern hemisphere of the solar system's heliosphere is being pushed in. Voyager 2 is the second spacecraft to enter this region of the solar system, behind Voyager 1, which reached the northern region of the heliosheath in December 2004."
This discussion has been archived. No new comments can be posted.

Voyager 2 Shows Solar System Is "Dented"

Comments Filter:
  • Shape? (Score:4, Interesting)

    by TitusC3v5 ( 608284 ) on Wednesday December 12, 2007 @06:32AM (#21669067) Homepage
    Could somebody explain how exactly the solar system has an innate 'shape'? I would think that that would be human-defined, not an actual, measureable feature.
    • Re:Shape? (Score:5, Interesting)

      by Kranfer ( 620510 ) on Wednesday December 12, 2007 @06:37AM (#21669085) Homepage Journal
      Its not the solar system that is dented but its far reaches where the solar wind suddenly slows down that is 'dented'. Figure a magnetic field or a sphere that is effected by its environment and causes it to lose its shape... The area where the solar wind slows down changes in shape due to interstellar influences... gasses, magnetic fields, etc... From a few articles I read on this the other day Voyager 2 passed through the terminal shock numerous times so far and will again in 2008 because it is constantly changing shape. Although I may be wrong, and I have been up all night sick and decided to go into work at 4 am... I dunno what the hell is wrong with me lol.
      • Re: (Score:3, Interesting)

        by Gabrill ( 556503 )
        Ok how long apart are these 2 (count them 2) points of reference? V2 also crossed the boundary what, 5 times? It seams to me that this could be stronger evidence that the whole thing fluctuates in size, rather than having a hard, irregular boundary.
        • Re: (Score:1, Redundant)

          by shokk ( 187512 )
          Going to go out on a limb here and guess that this has to do with our sun's solar cycles. But also which star systems have passed through these areas of the galaxy thousands of years before us, and of course, their solar cycles. Next year, or 20 years after, the other side could be squashed. I think it probably more resembles a flame.
        • Re:Shape? (Score:4, Informative)

          by Anonymous Coward on Wednesday December 12, 2007 @10:05AM (#21670111)
          This is the common method of viewing what termination shock is on earth: go to a sink and turn it on, as you will see in the basin, when the water hits, its ejected out on all sides. On the outskirts of the basin, where the water is forced by gravity back down, the water will become regular, non-moving, etc. This is the interstellar medium, the ambient pressure from outside our solar system is pushing against the solar wind (the water thats rushing away from its impact location) creating a location thats called termination shock. This location, as you can clearly see, is moving, always fluctuating. It changes its shape in response to the outside pressure (which here on earth, is caused by gravity wanting to pull the water down in the basin). You can probably easily see how a object could pass this boundary several times, especially when you realize that our solar system is much, much bigger then this example. A dented shock boundary could occur when, for whatever reason, the rushing water is being pushed back sooner. Perhaps there is more pressure on that side, or, in the case of space, you have some magnetic influences acting against the solar wind. Granted there could be other reasons, but the smart minds of today say its probably magnetic influences.
        • It seams to me that this could be stronger evidence that the whole thing fluctuates in size, rather than having a hard, irregular boundary.

          Small weather-like fluctuations at the periphery of this Zone are normal, but it only fluctuates wildly when there is some kind of a malignant, evil force that needs to be neutralized. The only question is how deep Earth is within the Unthinking Deeps.
          • by mmdog ( 34909 ) *

            ...The only question is how deep Earth is within the Unthinking Deeps.
            I've often pondered that question and my gut always tells me we are pretty deep. Seems almost like we are sinking deeper every day...
    • Re:Shape? (Score:5, Interesting)

      by MichaelSmith ( 789609 ) on Wednesday December 12, 2007 @06:38AM (#21669095) Homepage Journal

      Could somebody explain how exactly the solar system has an innate 'shape'? I would think that that would be human-defined, not an actual, measureable feature.

      Well the Sun has an innate shape. It is mostly a sphere, flattened a little bit by rotation. Other factors such as magnetic fields will play a part.

      The solar wind is really the outer part of the sun, so in one sense we are embedded in the sun, and it flows around our planet. It has long been expected that the solar wind would meet the interstellar medium at some sort of bow shock on the upstream side with a tail of sorts on the downstream side.

      This article suggests that magnetic fields which exist between stars also affect the shape of the boundary between the solar wind and whatever is outside it. Instruments on the Voyager spacecraft tell us which medium it is in at any point in time.

    • Re:Shape? (Score:5, Insightful)

      by Chuck Chunder ( 21021 ) on Wednesday December 12, 2007 @06:51AM (#21669149) Journal
      It is human defined in a sense, however the humans in question aren't arbitrarily picking a point, they are basing the definition on a measurable physical property, ie the area where the Sun's magnetic field has a (dominating) effect.
    • Re:Shape? (Score:4, Informative)

      by entrigant ( 233266 ) on Wednesday December 12, 2007 @06:54AM (#21669169)
      See: http://en.wikipedia.org/wiki/Heliosphere [wikipedia.org]

      Basically the suns solar winds push back interstellar matter. This can have a shape.
      • Re: (Score:3, Funny)

        by rucs_hack ( 784150 )
        Basically the suns solar winds push back interstellar matter. This can have a shape.

        So what your saying is, out there in interstellar space is a giant space kitteh saying 'I has a shape, let me apply it to you'.

        If it drops some giant space kitteh kibble while doing this, we are so screwed..
    • human defined? (Score:5, Insightful)

      by someone1234 ( 830754 ) on Wednesday December 12, 2007 @07:16AM (#21669253)
      Hmm? Is there anything known to us humans, that isn't human-defined?
      • by somersault ( 912633 ) on Wednesday December 12, 2007 @07:32AM (#21669317) Homepage Journal
        McDonalds?
      • Re: (Score:3, Interesting)

        by orclevegam ( 940336 )
        Pi? I've certainly never seen a complete definition of it, only approximations.
        • Complete definition of pi:

          4 * sum(i=1 to infinity) { (-1)^(i-1) (1/i) }

        • Re: (Score:3, Informative)

          by AeroIllini ( 726211 )
          Except those approximations of pi are expressed in (usually) base-10 notation, which is a human-created construction.

          Asking if there is something that exists that is not defined by humans is a tricky question. All of these things "exist", but all the tools we have for sensing them and measuring them are largely based on human-defined systems of measurements. We can't talk about these things without resorting to standards of measurement, which are wholly arbitrary and based on human experience.

          So, yes, there
    • It has paint primer, rust, no hub caps and dirt in most places too. No surprise there. Have you seen some of the low life beings that live in there?
  • Voyager 2's data is scientifically exciting for a number of reasons, NASA said. The spacecraft has a working plasma instrument that can directly measure the velocity, density and temperature of the solar wind. A similar instrument on Voyager 1 stopped functioning long ago.

    Voyager scientists had expected the temperatures within the termination shock to be about 1,000,000 degrees Fahrenheit (555,500 C) as material normally slows down and is heated up when it encounters an obstacle in a normal shock wave.
  • I, for one... (Score:5, Interesting)

    by sammydee ( 930754 ) <{moc.liamg} {ta} {todhsals+samdavies}> on Wednesday December 12, 2007 @06:33AM (#21669071) Homepage
    Actually think it's awesome that even twenty YEARS after it's launch, voyager 2 [wikipedia.org] is STILL doing useful science. Another thing that astounds me is how the engineers managed to ensure that even after all these years in the hostile environment of space, this machine is still perfectly functional.
    • Re: (Score:3, Funny)

      by Kranfer ( 620510 )
      I find it amazing as well. However, I know that someday Voyager will stop functioning and will shut down from lack of nuclear fuel... or be destroyed by Klingons... or even return to Earth is a horrible epic adventure involving the Enterprise....
      • by Briareos ( 21163 )
        Or it'll get destroyed crashing into a Krenim time warship, followed by the timeline changing so it'll never have happened and everyone living happily ever after...
      • STOP! Geek time-

        or be destroyed by Klingons...

        That was a Pioneer, not Voyager. You can tell by the plaque; I think non-canon lit rules it Pioneer 11.

        or even return to Earth is a horrible epic adventure involving the Enterprise....

        Did you ever see the director's cut DVD that came out a few years ago? It's a much better film, still a bit slow, but the visual effects are much better -- and were restored in a manner in keeping with the original concepts -- and now I think it's the best of the odd-numbered Treks. The cuts they made, the proper sound mix and the good visuals let you focus a lot more on the story

        • You've made a conscious comparison of odd-numbered Star Trek films...

          Please hand in your old geek card and accept this jewel-encrusted platinum VIP pass. Your lifetime achievement award is in the mail.
        • by Kranfer ( 620510 )
          ZOMG You ruined my joke :( I get emo on you now! ::whines::
    • by MichaelSmith ( 789609 ) on Wednesday December 12, 2007 @06:46AM (#21669119) Homepage Journal
      • Temperatures are extremely stable, so there is no expansion or contraction
      • Your electronics can't get rained on or filled with dust
      • There are no rats to eat your wires (yet)
      • There are no engineers around to fiddle with it and improve it (yes I know this does happen to software)
      • Cold is generally good for equipment, but not too much of course.
      • Your chance of being hit by a meteor is probably less than on Earth
      • etc

      If I ever do the transhuman thing and get turned into software, The Oort cloud is where I would want to be for serious durability.

      • Although its only a matter of time before Mynocks get to it. :)
      • by coinreturn ( 617535 ) on Wednesday December 12, 2007 @09:07AM (#21669735)
        Cold is generally good for equipment, but not too much of course.

        Actually, the "cold" of space doesn't help at all. Because the density of particles is so low, spacecraft can't cool down by convection. Cooling spacecraft (eg shedding internally generated heat) is a big problem. Also, the main "harsh" ingredient of space is radiation. The technology used in spacecraft is usually way behind commercial technology because it also has to be "rad-hardened."
        • by NateTech ( 50881 )
          Why do you call something that does its job well "behind"?

          Spoken like a PC salesman...

          Rad-Hardened CPU's and what-not are time-tested, and just work. A lot of the reason that they are "behind" isn't because new rad-hardened components can't be made (in fact they have), it's because satellite engineers have higher discipline levels when it comes to code-reuse and risk-management of software.

          Using an old chip (if it's fast enough and meets other requirements) with code that has not caused a failure of any mu
          • Why do you call something that does its job well "behind"? Spoken like a PC salesman...

            Hey, there's no reason to start name-calling! If you re-read my post, you'll see the thrust of my message was about cooling, not modern hardware. I mentioned "behind" because it takes years for new technology to be in enough demand for manufacturers to "bother" with rad-hard stuff. Yes, "behind" hardware can often do a great job, but often the new tech is much lower power (very important in space) due to shrunken geomet
    • by Eternauta3k ( 680157 ) on Wednesday December 12, 2007 @06:54AM (#21669165) Homepage Journal
      Actually, voyager 1 and 2 stopped working after a few months, current "findings" are just invented by NASA.
  • Obviously (Score:5, Funny)

    by Anonymous Coward on Wednesday December 12, 2007 @06:39AM (#21669099)
    Obviously, the reason the solar system is dented is because God dropped it.
  • Dented? (Score:3, Funny)

    by Centurix ( 249778 ) <centurixNO@SPAMgmail.com> on Wednesday December 12, 2007 @06:41AM (#21669111) Homepage
    Good job we have third party insurance on this sucker, I'd hate to see what we hit...
  • that the birthplace of Arthur, Sector ZZ9 Plural Z Alpha, contains something that appears Dent(ed).
  • They sure don't make 'em like they used to. Of course, this isn't the first time I've heard of the Voyager probes, but I am amazed every time I read a story about them. Thirty years old and still flying through space taking measurements. Absolutely amazing.
  • by Anonymous Coward on Wednesday December 12, 2007 @07:10AM (#21669231)
    AFAICT, they have one data point on the surface of the 'sphere'. Using that one data point they decide that the sphere isn't spherical. If they had a hundred Voyagers all leaving the solar system in different directions at the same time, I would be more convinced.
    • by andphi ( 899406 ) <phillipsam.gmail@com> on Wednesday December 12, 2007 @08:10AM (#21669453) Journal
      Actually, they seem to base their conclusion on the fact that Voyager 1 and Voyager 2 don't seem to have entered the termination shock at the same distance from the earth.

      FTA:

      "Voyager 2 entered the termination shock almost 1 billion miles closer within the southern hemisphere of the heliosphere of the solar system than Voyager 1 previously had," said Voyager Project scientist Edward Stone of the California Institute of Technology.
      • by MikeyVB ( 787338 ) on Wednesday December 12, 2007 @08:29AM (#21669525)

        Actually, they seem to base their conclusion on the fact that Voyager 1 and Voyager 2 don't seem to have entered the termination shock at the same distance from the earth.

        Actually, they seem to base their conclusion not only on that fact, but also because they had theorized that it might be that way from computer models that predicted when Voyager 1 and Voyager 2 reached the termination. So far Voyager 1 (actually, not sure on V1) and Voyager 2 reached the termination shock around where they thought they would according to the model that the Solar System is asymmetrical as described in TFA. (This [www.cbc.ca]arcicle briefly mentions the computer model)

    • Two data points, surely? And if they're right, they expect more in the future...
    • They have two data points: where V1 and where V2 crossed into the heliopause.

      And that's enough. If the heliosphere were a sphere, then by definition every point on its surface would be equidistant from the Sun. Now that they know two points are not equidistant from the Sun, they know it's not a sphere.

      What they don't know is how big the "dent" is. It could be no bigger than the spacecraft, of course, although that is extraordinarily unlikely. Or it could be enormous. This is probably what you mean: they
  • My bad (Score:3, Funny)

    by commodoresloat ( 172735 ) * on Wednesday December 12, 2007 @07:17AM (#21669255)
    Sorry folks, this was my fault. The folks were out of town and I figured I'd take the solar system out for a spin. I took a hard right to dodge a black hole and one thing led to another... Anyway, sorry about the dent; I'll pay for the damage.
  • Halp! (Score:5, Insightful)

    by Fizzl ( 209397 ) <fizzl@@@fizzl...net> on Wednesday December 12, 2007 @07:26AM (#21669291) Homepage Journal

    southern hemisphere of the solar system's heliosphere

    Could someone remind me how to orientate myself in the universe?
  • "Very Good - Looks fine at arm's length, but looking closer reveals soft corners and other imperfections."

    There goes our hopes for a near mint Solar System.

    Someday we'll finally end destroying the Earth and start with the rest. This gives us a head start.
  • by yagu ( 721525 ) * <yayagu@[ ]il.com ['gma' in gap]> on Wednesday December 12, 2007 @08:08AM (#21669449) Journal

    Should have parked farther out, not close to any other solar systems. Probably won't even meet the deductible.

  • It's good to know that the grocery store won't charge full price for our solar system.
  • RE: "Voyager 2 Shows Solar System Is "Dented", and "our solar system is not round"
    The Wikipedia entry for "Solar System" has a bunch of silly stuff about planets and moons and asteroids and other useless stuff, so I've deleted it all and replaced it with the much more informative: "not round, but Round-ish" ...update: Grrr... some wiki-fanboi perfectionist editor has corrected it to read "sphere-ish" ... oh well, at least my edit has a reference source so I guess I'll just take it up with Jimmy Wales
  • My question is how Voyager 2 can stand the thermal shock. The article reports that the temperature is something around 200,000 degrees. They are actually talking about the temperature of the "ions" but I would think that would damage the probe?

    I know we are not talking ambient temperature which would vaporize the probe. How dense is the matter and how do you measure this kind of energy?
    • Re: (Score:3, Interesting)

      by fbjon ( 692006 )

      How dense is the matter and how do you measure this kind of energy?
      Very sparse. With a thermometer.
    • isn't much (Score:3, Informative)

      by Quadraginta ( 902985 )
      Matter is unbelievably thin out there. Roughly 1 atom every 10 cubic centimeters. By contrast the best vacuums we can produce on Earth (around a trillionth of an atmosphere) contain 250 million atoms in every 10 cubic centimeters.

      It doesn't damage the spacecraft because, as anyone who has put out a candle flame with his fingers can tell you, it's not temperature that is dangerous but heat. Things with very little heat to transfer -- in this case, some unbelievably tiny amount of matter -- but at very hi
  • It's like.... (Score:1, Redundant)

    by argStyopa ( 232550 )
    ...millions of personal-injury lawyers cried out in pleasure at the idea of the galaxy's largest class-action damages lawsuit, and were suddenly silenced - by realizing that simply serving the summons on that bastard Fomalhaut (we know it was him, he's always been a troublemaker) would take longer than their lifespans.

    Nevertheless, I'm sure a few are planning to file anyway this morning, "just in case".
  • that the thing has been functioning for 30 years, in such conditions.* All the star trek shows have made us immune to the amazement of such a feat. I mean this thing traveled to the edge of the solar system, we can't begin to comprehend that distance....that's gotta be at least some 30-40 light seconds away from the sun.
    It traveled a huge distance, over a rather large period of time, and it still function.
    if that doesn't desrve a 'WOW'** that i don't know what does.

    *No MS/Linux jokes please
    **No World of Wa
    • Re: (Score:2, Informative)

      I ANAAP but Earth is 8 Light minutes from the sun...so I would suspect we are talking an hour or so.

      • oh right...right...i thought it was 8 seconds

        still an hour....even more amazing
        you look at the sun, and that's a sun from an hour ago....if sun disappeared you would still see it for an hour. It's an old realization, that quite a few stars I see at night don't even exist anymore.

        This is not a new fact to me, but it never ceases to amaze me. Puts everything in perspective somehow. Just proves to you if you see something it doesn't really mean it's there or it even exists anymore. BTW Anyone got a clue how lo
      • by yeremein ( 678037 ) on Wednesday December 12, 2007 @10:16AM (#21670205)
        This article [newscientist.com] says it's 84 AU out, which is a little more than 11.6 light-hours [google.com].
    • >that's gotta be at least some 30-40 light seconds away from the sun.

      I'm not sure if that was tongue-in-cheek, but the signal round-trip time to the voyagers are over 29 hours for V1 and closing on 24 hours for V2. Distance, in other words, is roughly 15 & 12 light _hours_. Heck even the sun itself is 8 light-minutes away. 30-40 light-seconds isn't very far, really.
  • it's not dented, it just needed a hug. [pbfcomics.com]
  • by Genom ( 3868 ) on Wednesday December 12, 2007 @10:07AM (#21670135)
    Looks like the Prince has some rolling to do.
  • Better get Maaco! http://www.maaco.com/ [maaco.com]
  • When was the last time we launched something with an intended lifespan of 30+ years? I can't recall (not to say that there *aren't*) any projects in the past 10-20 years. Granted, Spirit may end up running for a total of 30 years, but it's been running unexpectedly for a while already, and had no intentions of running for 1 year, let alone 30.

    Is there any way to get the US public behind a long-term investment like the Voyagers again?
  • Maybe it's a rental and came like this?
  • People should realize that this "dent" is in a heliopause with a density of maybe 1 atom per cubic centimeter - in other words, a much
    better vacuum than any on Earth. The solar wind blows up a huge "bubble" in galactic space, and Voyager is just getting to the edge of it.

    It is interesting but hardly surprising that so tenuous a gas so far from the Sun is buffeted by the even more tenuous gas flowing in the galaxy.
  • This is why we can't have nice things.
  • I just glad that it didn't get lost in the Delta Quadrant as well!
  • Never buy a solar system without a starfax history report....

The Tao is like a glob pattern: used but never used up. It is like the extern void: filled with infinite possibilities.

Working...