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Voyager 2 Shows Solar System Is "Dented"

Posted by kdawson on from the folded-spindled-mutilated dept.

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."

29 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.

      --
      http://michaelsmith.id.au
    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 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.

    --
    This is how the loudness war is killing music.
    1. 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?

    --
    http://michaelsmith.id.au
  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.

    --
    http://michaelsmith.id.au
    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. 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)

  9. 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
  10. 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?
    --
    Bot Assisted Blogging
    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..."
  11. 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.
  12. 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.
  13. 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.

  14. 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?