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Space Science

Voyager 1 Reaches Interstellar Space 565

letxa2000 writes "CNN is reporting that Voyager 1, now some 8.4 billion miles (90 AUs) from the sun, has left the solar system and entered interstellar space by reaching the heliopause. However, whether the probe has reached the heliopause or is just coming close is the subject of two papers to be published in Thursday's Nature Magazine. The probe supposedly has enough nuclear fuel to last until 2020. Will it be able to find anything interesting outside the solar system in the next 17 years?"
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Voyager 1 Reaches Interstellar Space

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  • by KFury ( 19522 ) * on Wednesday November 05, 2003 @04:51PM (#7399957) Homepage
    Do you guys have any idea how much RAM had to be added to the Matrix to extend the simulation out that far?!
  • to paraphrase (Score:3, Insightful)

    by Matey-O ( 518004 ) * <> on Wednesday November 05, 2003 @04:51PM (#7399958) Homepage Journal

    Will it be able to find anything interesting outside the solar system in the next 17 years?

    Short answer: No.

    Long Answer: "Space is big. Really big. You just won't believe how vastly hugely mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space... " -DNA

    • Re:to paraphrase (Score:5, Interesting)

      by Carnildo ( 712617 ) on Wednesday November 05, 2003 @04:56PM (#7400028) Homepage Journal
      Detailed answer: Yes.

      Questions that can still be investigated by Voyager include a number of questions about the interaction between the solar wind, solar magnetic field, and interstellar medium, direct measurements of the interstellar magnetic field, the actual composition of interstellar gas, where exactly the heliopause lies, and how it's affected by changes in solar activity. I'm sure there are even more questions that I haven't thought of.
    • Voyager will find the long lost Weapons of Mass Destruction, and Rumsfeld will use this as an excuse to overhaul the space program! We all know the Iraqis have had a secret space program since 1950.
    • Re:to paraphrase (Score:5, Interesting)

      by pclminion ( 145572 ) on Wednesday November 05, 2003 @05:22PM (#7400377)
      Better answer: We really hope so!

      Voyager has been moving through space in ways unexplainable by physics. There is a small acceleration that can't be accounted for using known laws. It's almost like gravity doesn't work quite the way we think it does.

      Of course, there is always the possibility that we just can't see the source of the acceleration, and it'll turn out to be something simple. However so far, all proposals put forth to explain it have been shown to be incorrect.

      There is a deeper connection to very important issues in physics. For decades we have been studying the fabled "dark matter" which is supposed to be the cause of the anomalous rotation of the galaxy. The galaxy does not move in ways predicted by the laws of gravity. It is as if there is a huge amount of hidden mass which is influencing its rotation. So far we have not found any of this "dark matter."

      But imagine the possibility. What if dark matter doesn't really exist? What if it's our understanding of gravity that is wrong? This would have profound implications throughout physics. After all our only direct experience of gravity is what happens here on Earth and within the bounds of the solar system. Except that today, we have a probe that has crossed that limit.

      Perhaps the anomalous motion of Voyager will shed light on the situation. I for one would be utterly elated if it turns out we have to rewrite our physics books.

      Voyager isn't useless yet!

      • Actually it's pretty well understood that our theory of gravity is wrong. It doesn't agree with quantum mechanics. That's the big push in physics right now to find a 'quantum' theory of gravity, or identify the graviton particle.
        • Re:to paraphrase (Score:3, Insightful)

          by pclminion ( 145572 )
          Well, there's a difference between being correct and being accurate. Yes, clearly our current theory of gravity is not CORRECT because it doesn't play well with QM. However it is a very ACCURATE theory in the sense that it gives answers which match reality exceedingly well (unless you take things to the quantum scale).

          What we're talking about here is a new situation, where the current theories of gravity aren't giving the right numbers even at a macroscopic scale. That is, if there isn't some other hidden

      • Re:to paraphrase (Score:3, Informative)

        by KjetilK ( 186133 )

        Voyager has been moving through space in ways unexplainable by physics.

        Any references I can read? astro-ph will do fine... :-)

        So far we have not found any of this "dark matter."

        Oh yes, there are many detections of massive astrophysical compact halo objects in our galaxy, P. Popowski et al [], and there is also a lot of work going on to use the same ideas to look for similar bodies in other galaxies. In fact, the microlensing ideas were first proposed for extragalactic studies by Chang and Refsdal i

    • from-JPL.NASA [] "The solar system does not end at the orbit of Pluto, the ninth planet. Nor does it end at the heliopause boundary, where the solar wind can no longer continue to expand outward against the interstellar wind. It extends over a thousand times farther out where a swarm of small cometary nuclei, termed Oort's Cloud, is barely held in orbit by the Sun's gravity, feeble at such a great distance. Voyager 1 passed above the orbit of Pluto in May 1988, and Voyager 2 will pass beneath Pluto's orbit i
  • Goodness... (Score:5, Funny)

    by swordboy ( 472941 ) on Wednesday November 05, 2003 @04:54PM (#7399985) Journal
    They've gone to plaid.
  • Heliopause (Score:5, Informative)

    by Anonymous Coward on Wednesday November 05, 2003 @04:54PM (#7399987)
    From Wikipedia, the free encyclopedia.

    The heliopause is the boundary where our Sun's solar wind is stopped by the interstellar medium.

    The solar wind blows a "bubble" in the interstellar medium (the rareified hydrogen and helium gas that permeates the galaxy). The point where the solar wind's strength is no longer great enough to push back the interstellar medium is known as the heliopause, and is often considered to be the outer "border" of the solar system.

    The distance to the heliopause is not precisely known. It is probably much smaller on the side of the solar system facing the orbital motion through the galaxy. It may also vary depending on the current velocity of the solar wind and the local density of the interstellar medium. It is known to lie far outside the orbit of Pluto. The current mission of the Voyager 1 and 2 spacecraft is to find and study the heliopause.

    An alternative definition is that the heliopause is the magnetopause between the solar system's magnetosphere and the galaxy's plasma currents.
  • by Anonymous Coward isn't going to reach the delta quadrant anytime soon?
  • by sielwolf ( 246764 ) on Wednesday November 05, 2003 @04:54PM (#7399995) Homepage Journal
    Aliens too stupid to wipe off some space dirt to realize the dang thing isn't named VEEEGERRRR!
  • by yndrd ( 529288 ) on Wednesday November 05, 2003 @04:54PM (#7399996) Homepage
    What's the range of communications for the probe? When will we lose our connection (if we haven't already)?
    • by Carnildo ( 712617 ) on Wednesday November 05, 2003 @05:00PM (#7400070) Homepage Journal
      What's the range of communications for the probe? When will we lose our connection (if we haven't already)?

      No one knows for certain. A number of factors enter in, including the ability of Voyager to keep its antenna pointed at Earth, the amount of power left in the radiothermal generator, the size of radio telescope available for communicating with it on Earth, and possibly unknown effects from the heliopause.
    • by leerpm ( 570963 ) on Wednesday November 05, 2003 @05:02PM (#7400096)
      Yes, the US government has a secret message it uses to identify this point:

      "Can you hear me now? .. Can you hear me now?"
    • by N7DR ( 536428 ) on Wednesday November 05, 2003 @05:20PM (#7400351) Homepage
      What's the range of communications for the probe? When will we lose our connection (if we haven't already)?

      For many years I was a co-investigator on Voyager (actually, technically, I suppose that I still am; I have never been notified that the status ever changed). Anyway, the best guess when I was an active participant, throughout the 80s and half of the 90s, was more-or-less the year 2010. That was predicted to be the year at which the always-decreasing power output from the transmitter, the ever-increasing distance and the more-or-less constant sensitivity of the DSN (Deep Space Network) system combined to reduce the received signal to the point where it the bit rate at which information could be extracted was too low to be useful.

      The general supposition was that funding would be eliminated before that date.

      • by Not_Wiggins ( 686627 ) on Wednesday November 05, 2003 @05:38PM (#7400534) Journal
        I suppose if they felt they were still getting useful information from the probe (ie, it was "looking" at something "interesting" with sensors that still worked), they could always launch a relay-type satellite... just like a network repeater.

        Good thing they have several years to decide both if they:
        A) want to have/fund such a thing
        B) are getting new information worth collecting

        Heck... who knows where our terrestrial (or even space-stationed) receiver technology will be in 5 years; perhaps we'll be able to pick out the signal from here, no matter how weak nor how noisy.
        • you cant launch a relay satellite. Remember, the falloff is r^2. Even the best engines would take about 10 years to place a satellite halfway between voyager and earth.
          that would be 2015 or so. Now the energy density at the point of the satellite would be 4 times as high as on earth, BUT there is no way you can stuff a reviever on a satellite who as 5% of the sensitivity of a earth based reciever. Remember, on earth you could use 300m at arichbo. For 4 times the signal power, you would still need a 150m dis
        • by StewedSquirrel ( 574170 ) on Wednesday November 05, 2003 @07:46PM (#7402022)
          First of all, the primary issue with the signal falloff is the SIZE of the reciever. Launching a sattellite doesn't exactly solve that problem, because the sattelite's reciever would have to be *nearly* as large as the VLA or the big "lake sized" earth-bound dishes.

          I think it has more to do with the sheer size, than the sensitivity of the reciever. The "noise" from the Universe will eventually eat the signal and with the combination of decreasing power and increasing distance, I think xmit power will fall off faster than some "technology" (new filters, transforms, etc etc)

    • by gad_zuki! ( 70830 ) on Thursday November 06, 2003 @08:06AM (#7405742)
      >When will we lose our connection (if we haven't already)?

      Its good until 2005 when the FCC Broadcast Flag rule makes recieving the signal illegal without a DRM upgrade.
  • communicating? (Score:2, Insightful)

    by wankledot ( 712148 )
    if it does find anything, how long before it's out of earshot for us? Are we able to hear from it up until that last bit of fuel is spent?
  • Heliopause (Score:4, Funny)

    by mongoks ( 540017 ) on Wednesday November 05, 2003 @04:56PM (#7400021)
    Voyager 1 has reached heliopause and is now experiencing hot flashes and irritability. Hormone replacement therapy has proven innefective thus far.
  • Fuel running out (Score:2, Interesting)

    What is this fuel used for? Just for communicating, or does it still need acceleration? If it's just for communication, couldn't they make it last longer by increasing the intervals between each time it communicates?

    • It's just used for sensors and communication, but it's a nuclear fuel, and it's goiong to decay whether we use the energy or not. Plutonium's half-life is Plutonium's half-life, and there's not anything we can do about that...
    • I should hope its doing more than just communicating its existence to us. While it may not need to accelerate (it may, I don't know), it does have various instruments on it for measurements and observations, so that it has something to communicate to us beyond a simple "Hello."
      • It's only got a few things it needs to do: keep the antenna pointed (roughly) at Earth, run the few instruments still active (the camera, for example, has been turned off), and occasionally communicate.
    • Re:Fuel running out (Score:5, Informative)

      by BengalsUF ( 145009 ) on Wednesday November 05, 2003 @05:02PM (#7400097)
      Voyager uses a radioisotope thermoelectric generator for its power. This means that radioactive decay of its fuel creates heat, which is used to create power. That fuel's going to decay no matter what, so you either use the power or lose it.
    • Re:Fuel running out (Score:3, Informative)

      by zakezuke ( 229119 )
      What is this fuel used for? Just for communicating, or does it still need acceleration? If it's just for communication, couldn't they make it last longer by increasing the intervals between each time it communicates?

      I believe they are talking about the nuclear battery that's onboard to power it's 20watt transmitter. Near as I remember the decay of plutonium causes heat which keeps the craft warm and operational, and is used to generate power. Given that this was launched in 1978, this is a major acco
  • The Heliosphere (Score:4, Informative)

    by UrgleHoth ( 50415 ) on Wednesday November 05, 2003 @04:56PM (#7400027) Homepage
    NASA's page on the heliosphere []
  • 12.5 Hours (Score:5, Interesting)

    by johnos ( 109351 ) on Wednesday November 05, 2003 @04:57PM (#7400031)
    That's how long it takes a signal to reach us from the probe. When you consider the galaxy is 100,000 light years across, 8.4 billion miles is nothing.
  • so that when V'ger comes back, we'll know what it is. I'm uncomfortable placing the fate of the Earth in the hands of James T. Kirk again.
  • by downix ( 84795 ) on Wednesday November 05, 2003 @04:59PM (#7400048) Homepage
    of how scientists do not take the next big leap. What frightens me the most is that we have not sent more probes after Voyager.

    Coming up is a planetary alignment that would allow a route to Tau Ceti, one of the reasonably nearby stars that could have an inhabitable planet. Using modern high-velocity nuclear engines, a probe could be engineered to reach it in 100 years, roughly. And a craft could be engineered to actually survive the travel *and* send back useful data.

    I want to see interstellar probes, engineered to travel to the nearest (12ly or less) stars and explore them.
    • Funny thing about large timeframes and technology -- if you wait long enough you will actually be further ahead.

      Exploring this solar system with experimental high-velocity nuclear engines is appropriate. But in 20 years we could probably send something to the nearest stars in 50 years. In 40 years perhaps it will only take 25 to travel -- thus we should wait 40 years before launching to arrive first :)
  • by _Sambo ( 153114 ) on Wednesday November 05, 2003 @05:00PM (#7400072)
    90 AUs (Distance from the Sun to the Earth)
    8 minutes (Time it takes light to reach Earth from the Sun)
    720 Light Minutes
    12 Light Hours.

    We're quite a ways away from the Light Year.
  • by tjstork ( 137384 ) <todd.bandrowsky@gma i l .com> on Wednesday November 05, 2003 @05:01PM (#7400082) Homepage Journal

    says: "Doh, Stupid comet!"

    20 years from now, against all odds, the comet bashed ever so slightly by our irresponsibly launched space probe slams into Yellowstone super volcano.

    That little probe has to be stopped before it bumps into something! Send someone out to get it before it's too late!

  • by Jesrad ( 716567 ) on Wednesday November 05, 2003 @05:04PM (#7400120) Journal
    I wonder if we'll ever see space technology advance enough so that, one day, we might be able to send a spacecraft past Voyager. Maybe we'll have some form of near-light-speed travel, or even faster-than-light travel, and manage to reach other stellar systems before Voyager does ?

    In any case, I'll be more than satisfied if we establish a colony on Mars, tag me a conservative if you will, but I don't feel like leaving good old Sol just yet.
    • ... expensive.

      The Voyager probes weren't built for speed. They were coasters, zipping from gravity well to gravity well with just a few puffs from the steering jets now and then.

      If there were some pressing reason to catch up, we could do it, although it would be pricey due to the current high cost of getting things into orbit. You'd need to get something up there with a motor capable of adding substantial change in velocity. A big liquid fueled motor, or perhaps one of those new-fangled ion drives powered
  • Here's hoping that the only pre-requisite for other species to be allowed to engage in interstellar contact with yours is to build a probe that leaves your solar system. Gort shoudl be arriving anyday now to lay down the law.
  • by MoeMoe ( 659154 ) on Wednesday November 05, 2003 @05:07PM (#7400155)
    Scientists have long theorized that a shock wave exists where the hot solar wind bumps up against the thin gas of the interstellar medium.

    Picard: To boldy go where no ma-, hang on Number 1, speed bump!

    Will: All hands embrace for impact...


    Picard: Data, inform engineering that we need better suspension on this thing...
  • thud (Score:2, Funny)

    by lecca ( 84194 )
    "The probe supposedly has enough nuclear fuel to last until 2020. Will it be able to find anything interesting outside the solar system in the next 17 years?"
    If it goes much further, I bet it hits the screen.
  • by da3dAlus ( 20553 ) <dustin,grau&gmail,com> on Wednesday November 05, 2003 @05:16PM (#7400284) Homepage Journal
    First Broadcast: "My god, it's full of stars!"

    Maybe now we'll find out how accurate that Starfield Simulation screensaver really is!
  • A song comes to mind (Score:3, Interesting)

    by IWantMoreSpamPlease ( 571972 ) on Wednesday November 05, 2003 @05:19PM (#7400329) Homepage Journal
    From the band Warlord:

    "Through Pioneer 10 and Voyager 1
    We've launched our knowledge to other suns
    Aspiring and reaching for the highest of beings
    We've lost our search for the world's basic needs"

    I hope it does find something, or something finds it. Earth could use some good news.
  • by Rasta Prefect ( 250915 ) on Wednesday November 05, 2003 @05:19PM (#7400335)
    In space, the violent encounter slows the solar wind from supersonic velocity to subsonic speed, and causes a pileup of particles.

    Last time I checked the speed of sound in space was essentially zero...

    • by pclminion ( 145572 ) on Wednesday November 05, 2003 @06:03PM (#7400845)
      Sorry but this is a pet peeve of mine.

      Indeed, science can be distilled down to a set of little sound-bite facts that are easily repeatable. "There is no sound in space" is one of them. However what most people for some reason do not understand is that this is a SOUND BITE.

      It is far too common for Slashdot readers to immediately object to something because it clashes with their boiled down kiddy version of science.

      Here's some news for you: the space surrounding the sun is far from empty, in fact it is filled with atoms, electrons, and ionized gas. Its density is low enough that a human would not perceive it without an instrument. But sound can quite easily travel through gas, no matter how thin. Clearly the sound cannot travel any faster than the individual particles themselves are moving. Hence it is very easy to define the speed of sound in a gas.

      No, I'm not claiming to be a scientist or above anyone else in terms of scientific knowledge, but it really pisses me off when people's first reaction is to DOUBT THE SCIENTISTS. Sure, they can be wrong sometimes, but I think it would be respectful to go do a little research before claiming, as if you are some kind of expert, that they are wrong.

  • What if.... (Score:4, Funny)

    by jgacad ( 705298 ) on Wednesday November 05, 2003 @05:22PM (#7400372) Journal
    the aliens that find voyager only have CD players? How will they play the record that strapped to the craft?

  • by Cassanova ( 578879 ) on Wednesday November 05, 2003 @05:50PM (#7400699)
    Voyager crash lands on this deep and remote each of its systems start to shutdown in turn, its external microphones pick up the voice of Charleston Heston, screaming in the distance "Take your paws off me you damn dirty ape!"....
    [muffled horse hooves pounding on the ground]
    Voyager 1 signing off. Goodbye earth...

"I don't believe in sweeping social change being manifested by one person, unless he has an atomic weapon." -- Howard Chaykin