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Ladies and Gentlemen! Voyager 1 Has Left the Solar System!

  1. Jun 20, 2012 #1
    Per NASA's press release ( http://www.nasa.gov/mission_pages/voyager/voyager20120614.html ) of 14 June 2012, interstellar cosmic rays are striking the spacecraft at an increased rate. Voyager 1 has already encountered solar wind moving laterally with respect to the solar surface, and even in net retrograde motion with respect to the solar surface, which would mean that she's passed through the limit of solar influence capable of deflecting the interstellar medium, and has observed the interstellar medium deflecting solar influence. If the density of charged particles in the vicinity of the spacecraft has INCREASED, then this can only mean that she is currently in the "bow shock", which is where interstellar winds would tend to pile up in front of the solar system as it flies through interstellar space. (Think of a ship passing through the water: water is incompressible, so the energy of the ship passing through the water can only be expressed as a shift in the volume of the water immediately adjacent to the ship's bow (the "bow wave"). In a similar fashion, interstellar winds would tend to pile up in front of the solar system as an expression of aerodynamic pressure/aerodynamic drag.) If she's within the "bow shock", then she's within the interstellar medium, and no longer within the solar system.

    Just think of that! An object crafted by human hands is now flying in interstellar space, outside the solar system! Elvis has truly left the building!

    Three cheers for Voyager 1:

    Hip! Hip! HOORAY!
    Hip! Hip! HOORAY!
    Hip! Hip! HOORAY!
  2. jcsd
  3. Jun 20, 2012 #2


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    That's way cool.
  4. Jun 20, 2012 #3
  5. Jun 20, 2012 #4


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    Wow. That sucker was launched the year I graduated from high school. What the hell has kept it going?

    google google google

    13 more years!

    That is freaking awesome. I'll be 66 years old, and probably ready for the permanap myself.

  6. Jun 20, 2012 #5
    Oh my damn...that is incredible!
  7. Jun 20, 2012 #6


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    [STRIKE]In space, it just coasts, so...[/STRIKE] :biggrin:
  8. Jun 20, 2012 #7
    The most shocking thing is that we can pick up a 24 Watt transmitter from this distance. I still can't beleive it.
  9. Jun 20, 2012 #8


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    Well they better hurry up and get it back soon...
  10. Jun 20, 2012 #9

    Anna Blanksch

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    That. Is. AWESOME! Hip Hip Hooray!
  11. Jun 20, 2012 #10
    I'm glad at least some of our race views this as important. This is the epitome of what our curiosity is capable of!
  12. Jun 21, 2012 #11
    It is quite a feat, but I can't help but think what we could achieve today. Although it's a bit of a vast distance to catch up to....
  13. Jun 21, 2012 #12
    I remember that launch. The roads were packed with thousands of protesters objecting to the nuclear payload. That craft has a nuclear reactor onboard for power. Too far away from the sun to use solar power.
  14. Jun 21, 2012 #13


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    It's not a nuclear reactor, its a radioisotope thermoelectric generator. The difference as I understand it is that the first involves induced chain reactions of nuclear fission and the latter is harvesting energy from the heat produced by continuous radiation.
  15. Jun 21, 2012 #14
  16. Jun 21, 2012 #15
    I know I'm a bit late, but awesome!
  17. Jun 22, 2012 #16
    O Wow it was great...didn't even knew about this.
  18. Jun 22, 2012 #17
    I know that a RTG is not a nuclear reactor, but it is commonly called that in the press, and we who worked with them would also sometimes call it that, even though we knew better.

    I worked in the lifting, handling, and installation into the spavecraft, so I was not one of the guys who got to see them on the inside.

    The radioactive material is only a passive heat source. It warms a bunch of thermocouples, which generate a voltage and current.
    Last edited: Jun 22, 2012
  19. Jun 22, 2012 #18
    I should have stated clearly in my original post that my statement on this matter represents a minority report, as the NASA people still say passage through the heliopause is yet to come. My statement is in accord with the criteria laid out for measuring passage through the heliopause and into the bow wave, which have clearly been satisfied per the measurements to which I refer in my original post.
    Last edited: Jun 22, 2012
  20. Jun 23, 2012 #19


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    For every distance, there is an ideal time to launch a probe to reach the destination :). For up to ~200 AU (and maybe more), I think Voyager will be first. And after that, I doubt that there are many interesting targets within 4 light years.
  21. Jun 24, 2012 #20


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    Every once in a while I've heard it said that the Oort cloud is part of the solar system, presumably traveling along with us a light year or so off. I've also heard from NASA that the heliopause defines the limit of the solar system. Who's right? Is it a fact or merely a surmise that the Oort cloud really even exists? What would it mean if it doesn't exist? Could Voyager, or any device, make the trip to the Oort cloud and still keep on ticking? What sorts of instruments would be needed to verify the Oort cloud?

    Respectfully submitted,
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