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Voyager 2 Shows Solar System Is "Dented"

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."

44 of 173 comments (clear)

  1. Shape? by TitusC3v5 · · Score: 3, Interesting

    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.

    --
    And the masses cried out, "09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0!"
    1. Re:Shape? by Kranfer · · Score: 5, Interesting

      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.

      --
      -- Josh
      "Whoopie! Man, that may have been a small one for Neil, but that's a long one for me!" - Pete Conrad
    2. Re:Shape? by MichaelSmith · · Score: 5, Interesting

      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.

    3. Re:Shape? by Chuck+Chunder · · Score: 4, Insightful

      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.

      --
      Boffoonery - downloadable Comedy Benefit for Bletchley Park
    4. Re:Shape? by entrigant · · Score: 4, Informative

      See: http://en.wikipedia.org/wiki/Heliosphere

      Basically the suns solar winds push back interstellar matter. This can have a shape.

    5. Re:Shape? by rucs_hack · · Score: 3, Funny

      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..

    6. Re:Shape? by Gabrill · · Score: 2, Interesting

      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.

      --
      Always going forward, 'cause we can't find reverse.
    7. Re:Shape? by Anonymous Coward · · Score: 4, Informative

      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.

  2. I, for one... by sammydee · · Score: 5, Interesting

    Actually think it's awesome that even twenty YEARS after it's launch, voyager 2 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.

    1. Re:I, for one... by Kranfer · · Score: 2, Funny

      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....

      --
      -- Josh
      "Whoopie! Man, that may have been a small one for Neil, but that's a long one for me!" - Pete Conrad
    2. Re:I, for one... by Eternauta3k · · Score: 5, Funny

      Actually, voyager 1 and 2 stopped working after a few months, current "findings" are just invented by NASA.

      --
      Yeah. Would you choose a neurosurgeon who pokes around people's brains in his spare time? I wouldn't.
  3. Obviously by Anonymous Coward · · Score: 5, Funny

    Obviously, the reason the solar system is dented is because God dropped it.

  4. Re:I don't get it by MichaelSmith · · Score: 4, Informative

    how does the spacecraft survive in those temperatures?

    The density is very low. The body of the spacecraft might get hit by individual molecules which have that temperature, but what are a few thousand molecules going to do to it?

  5. Dented? by Centurix · · Score: 3, Funny

    Good job we have third party insurance on this sucker, I'd hate to see what we hit...

    --
    Task Mangler
  6. Its not really hostile by MichaelSmith · · Score: 5, Interesting
    • 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.

    1. Re:Its not really hostile by coinreturn · · Score: 4, Informative

      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."

  7. Re:I don't get it by Anonymous Coward · · Score: 4, Informative

    Probably simple physics ... remember, the density of the gas in space is very low (almost non existant); this implies that there are very few particles hitting the craft at that temperature. Meaning that the craft only needs to have roughly 10000 times the density of space to operate at a "normal" temperature. Given the craft is made out of solid things like metal, that shouldn't be too hard...

  8. It seems logical by laejoh · · Score: 2, Funny

    that the birthplace of Arthur, Sector ZZ9 Plural Z Alpha, contains something that appears Dent(ed).

  9. Is this any better than conjecture? by Anonymous Coward · · Score: 4, Insightful

    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.

    1. Re:Is this any better than conjecture? by andphi · · Score: 4, Informative

      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.

    2. Re:Is this any better than conjecture? by MikeyVB · · Score: 4, Informative

      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. (Thisarcicle briefly mentions the computer model)

  10. human defined? by someone1234 · · Score: 4, Insightful

    Hmm? Is there anything known to us humans, that isn't human-defined?

    --
    Patents Drive Free Software as Hurricanes Drive Construction Industry
    1. Re:human defined? by somersault · · Score: 4, Funny

      McDonalds?

      --
      which is totally what she said
    2. Re:human defined? by orclevegam · · Score: 2, Interesting

      Pi? I've certainly never seen a complete definition of it, only approximations.

      --
      Curiosity was framed, Ignorance killed the cat.
    3. Re:human defined? by AeroIllini · · Score: 2, Informative

      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 are lots of things that exist that are not human defined. However, once we name it or measure it or look at it or smell it or hear it or touch it, we are ascribing human-created standards to it so we can describe it to other people. It is these standards of measurement which are defined by humans, not the things themselves.

      </philosophy>

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  11. My bad by commodoresloat · · Score: 2, Funny

    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.

  12. Halp! by Fizzl · · Score: 4, Insightful

    southern hemisphere of the solar system's heliosphere

    Could someone remind me how to orientate myself in the universe?
    1. Re:Halp! by JustOK · · Score: 5, Funny

      Up is the shortest distance out of your head. In most cases, its best if "up" is not in the same direction as the dominant gravity source.

      --
      rewriting history since 2109
    2. Re:Halp! by andphi · · Score: 3, Funny

      The Enemy's Gate is Down.

    3. Re:Halp! by Gabrill · · Score: 4, Informative

      Right hand rule. Fist your right hand, and the fingers indicate direction of spin. The thumb indicates North. Most of the Milky Way galaxy follows this rule, in conjunction with Earth (excepting Uranus, not a team player).

      --
      Always going forward, 'cause we can't find reverse.
    4. Re:Halp! by rb4havoc · · Score: 3, Funny

      So basically, Uranus is the Dennis Rodman of Planets?

      --
      "There are 10 types of people in this world--Those that understand binary, and those that do not..."
    5. Re:Halp! by TimeTraveler1884 · · Score: 2, Funny

      Most of the Milky Way galaxy follows this rule, in conjunction with Earth (excepting Uranus, not a team player).
      No kidding, that guy is a real ass.
  13. another ding in the solar system by yagu · · Score: 2, Funny

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

  14. Re:I don't get it by sqldr · · Score: 4, Interesting

    As an analogy, it's like smoking. You're breathing particles at up to 6000 degrees C, but it doesn't do (much) damage.

    --
    I wrote my first program at the age of six, and I still can't work out how this website works.
  15. I have updated Wikipedia to reflect this by thomasdz · · Score: 2, Funny

    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

    --
    Karma: Excellent. 15 moderator points expire sometime.
  16. Re:I don't get it by hey! · · Score: 4, Funny

    My hat is off to you. You, sir, are a master of irony.

    --
    Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
  17. Re:I just find it amazin by Technopaladin · · 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.

  18. Re:How does it stand the thermal shock? by fbjon · · Score: 2, Interesting

    How dense is the matter and how do you measure this kind of energy? Very sparse. With a thermometer.
    --
    True confidence comes not from realising you are as good as your peers, but that your peers are as bad as you are.
  19. King of All Cosmos went on a bender again... by Genom · · Score: 2, Funny

    Looks like the Prince has some rolling to do.

  20. Almost 12 light-hours, actually by yeremein · · Score: 4, Informative

    This article says it's 84 AU out, which is a little more than 11.6 light-hours.

  21. The Truth by ScotlynHatt · · Score: 3, Funny

    Okay folks, I have some bad news for you. Human space exploration is deforming the universe and stuff. You heard it here first. I declare this anomaly "Universal Warming." What's higher than the Nobel prize?

  22. Well that's just great. by El+Yanqui · · Score: 2, Funny

    This is why we can't have nice things.

    --
    Well, thanks to the Internet, I'm now bored with sex.
  23. I should have check.... by Lost+Penguin · · Score: 2, Funny

    Never buy a solar system without a starfax history report....

    --
    I am the unwilling control for my Origin.
  24. isn't much by Quadraginta · · Score: 2, Informative

    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 high temperature, are harmless.

    An analogous situation exists with respect to electricity: it isn't voltage per se that is dangerous to you but rather charge. Things that are at very high voltages (e.g. the static charge you built up when you scuff your shoes on a dry winter day) can be quite harmless if the amount of charge that can be transferred is very small, e.g. just a little spark.

    The confusion exists in part because usually things at high temperature (or high voltage) have plenty of heat (or charge) to transfer, and then they are more dangerous than equivalent reservoirs at lower temperature (or voltage), because they transfer the lethal dose of heat (or charge) much faster.