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More Spacecraft Velocity Anomalies

ZonkerWilliam recommends a bulletin from the American Institute of Physics, which discusses a study noting that recent spacecraft, such as NEAR, appear to display velocity anomalies much like those seen in Pioneer 10 (which were observed beginning ten years ago). The anomalies amount to up to 13 mm/sec., with a measurement accuracy of 0.1 mm/sec. Quoting: "A new look at the trajectories for various spacecraft as they fly past the Earth finds in each case a tiny amount of surplus velocity. For craft that pursue a path mostly symmetrical with respect to the equator, the effect is minimal. For craft that pursue a more unsymmetrical path, the effect is larger."

30 of 339 comments (clear)

  1. spooky by superdana · · Score: 5, Funny

    Does anyone else feel like they just read the first console in an old Bungie game? We should probably be arming ourselves.

  2. Recheck that gague by yotto · · Score: 4, Funny

    It's actually 13 inches per hogshead, which is what they expected.

    No problems here.

  3. Hmmm..... by TripMaster+Monkey · · Score: 4, Interesting

    Could this anomaly possibly be explained by dark matter?

    --
    ____

    ~ |rip/\/\aster /\/\onkey

    1. Re:Hmmm..... by sm62704 · · Score: 4, Funny

      Could this anomaly possibly be explained by dark matter [blogspot.com]?

      Maybe, but I think it's more easily explained by dork matter.

      There is no dork side of the moon. As a matter of fact it's all dork.

      --
      mcgrew's razor: Never attribute to stupidity that which can be explained by greedy self-interest
    2. Re:Hmmm..... by Leperous · · Score: 4, Insightful

      Unlikely. If "everything [were to] speed up" that would presumably include us, and hence we wouldn't be able to observe any difference. Plus, if this was happening, it should be more apparent faster moving objects, such as particles whizzing around particle accelerators at relativistic speeds - but it's not.

    3. Re:Hmmm..... by florescent_beige · · Score: 4, Informative

      According to this, the acceleration anomaly can't be accounted for by dark matter.

      --
      Equine Mammals Are Considerably Smaller
    4. Re:Hmmm..... by kestasjk · · Score: 4, Funny

      Lets postulate an entirely new field/form of matter/universe to explain this phenomenon!

      --
      // MD_Update(&m,buf,j);
    5. Re:Hmmm..... by macslas'hole · · Score: 4, Informative

      The Earth does indeed gain mass continuously from in-falling space dust, captured solar wind, etc., and as a consequence of GR, our clocks should be getting slower over time relative to distant satellites. However, I would think that the effect is not sufficient to account for the observed velocity discrepancy. I am just a lowly programmer, but I would be very surprised if those physicists have not taken this into account or discounted this accordingly.

      --
      Life's a tale told by an idiot, full of sound and fury, signifying nothing.
    6. Re:Hmmm..... by CheshireCatCO · · Score: 5, Informative

      I can't speak to this specific case, but someone did a study several years ago of the Voyager anomaly and whether it could be a gravitational effect. The gist of the analysis was the if it were gravitational, it would also affect the distribution of long-period comets, especially the "new" ones from the Oort cloud. They calculated the effect you'd expect and it's much too large relative to what we see in the comets, so whatever is affecting Voyager pretty much cannot be gravitational in nature.

      It's also worth noting that even in the mega-analysis by Anderson et al. concluded that although they couldn't determine a source for the anomaly, they still generally felt that it was more likely to be endogenic than exogenic.

    7. Re:Hmmm..... by Teancum · · Score: 4, Insightful

      One thing you must remember is that this is being published in scientific journals, not just some back page of your local newspaper. If there is one thing scientists do like to perform, is showing that somebody else missed a basic calculation on their raw data like you are suggesting. This is called "peer review", and very common in scientific journals... even if it is more informal than an organized panel. That is in fact why results like this are published in journals like this, so these kind of mistakes can be vetted.

      Or more to the point, if you want to make a name for yourself, look through the raw data, perform the calculations yourself, and show what mistake somebody with a PhD did with this sort of data. Many graduate students have indeed gained notice when they have performed exactly these sort of calculations.

      Have fun! Seriously, I mean it!

  4. Good excuse by Anne_Nonymous · · Score: 5, Funny

    I'm sorry officer; I was experiencing a velocity anomaly.

    1. Re:Good excuse by sm62704 · · Score: 4, Funny

      I'm sorry officer; I was experiencing a velocity anomaly.

      That's too bad, son, I'm still writing you a ticket. From now on keep it under 299,792,458 meters per second. The law is the law!

      --
      mcgrew's razor: Never attribute to stupidity that which can be explained by greedy self-interest
  5. An appropos quote by jandrese · · Score: 4, Insightful

    Someone once said: The most profound scientific discoveries never begin with EUREKA! Usually they start with the words "now that's odd..."

    --

    I read the internet for the articles.
    1. Re:An appropos quote by AndroidCat · · Score: 5, Funny

      I thought it was "Here, hold my beer."

      --
      One line blog. I hear that they're called Twitters now.
    2. Re:An appropos quote by ZaMoose · · Score: 4, Funny

      No, no, that's the way we get Darwin Award nominees.

      --
      I wish I had a kryptonite cross, because then you could keep Dracula and Superman away.
    3. Re:An appropos quote by tppublic · · Score: 4, Informative
      I believe you're referring to: "The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' but rather, 'That's funny...'"-Isaac Asimov

      Occasionally this is also quoted as ending with 'Hmm, that's funny'.

    4. Re:An appropos quote by MBGMorden · · Score: 4, Funny

      There's an old redneck joke in there somewhere. Something like 50% of deaths by rednecks are immediately preceded by "Hey ya'll, watch this!".

      Having grown up around (and most people would probably say as) rednecks, there's some weird level of truth to that. Who else can say that they know a guy paralyzed from the neck down from trying to steal a riding lawn mower from Wal-mart by using an extension cord to tie it to the back of his buddies pickup, and then trying to drive/be towed on the lawnmower down the road at 60+ mph. Lets just say he lost control a few miles down the road . . .

      --
      "People who think they know everything are very annoying to those of us who do."-Mark Twain
    5. Re:An appropos quote by camperdave · · Score: 4, Funny

      Some would say he lost control long before he ever got on the lawnmower.

      --
      When our name is on the back of your car, we're behind you all the way!
  6. well duh by circletimessquare · · Score: 5, Funny

    gravitons display a bias for polar rather than equatorial output. this was the basis for the graviton engine that first bought man...

    oh shit, forgot what time line was in, you guys aren't supposed to discover this until 2039. dang it, screwed up again. i'll have to shut this time line down...

    --
    intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
  7. Message from your gods by rbarreira · · Score: 5, Funny

    We're sorry about the bugs you've been observing lately. The latest anomalies are due to bug #14310, a hardware glitch much like those present in your own Pentium processors.

    We're trying as hard as we can to mitigate this issue, primarily by avoiding the use of floating point calculations in our physics engine. In the meantime, we're manually changing your physics books so that you'll be able to calculate the ship's movement correctly. In one day, you'll have no memory that this incident ever happened, so do not worry.

    --

    The AACS key is NOT 0xF606EEFD628B1CA427BEA93A9CA9773F
  8. I know what it is! by kiick · · Score: 5, Funny

    Once you leave Earth for a while, particularly if you travel far, you realize that it doesn't suck quite as much as you thought.

    A similar phenomenon occurs when traveling outside of the U.S.

  9. precision, not accuracy by rangek · · Score: 5, Informative

    The precision of the measurements is 0.1 mm/sec, not the accuracy. Those are different things.

  10. Re:Awesome precision by Detritus · · Score: 5, Informative

    The range isn't an issue, it's how accurately they can measure doppler. The standard technique is to transmit a special signal to the spacecraft, which retransmits it to the Earth, like an RF mirror. This allows them to use extremely stable ground-based oscillators, like Hydrogen masers. This signal can also be modulated with a PN code to allow precise range measurements.

    --
    Mea navis aericumbens anguillis abundat
  11. The specialization of knowledge... by Kagura · · Score: 4, Insightful

    Sadly, none of us can probably make a useful suggestion on this topic (one that would have eluded all the physicists that have been working on this). Unless the next Einstein is reading Slashdot,we can only make narrow conjectures. How many of us have the knowledge and data required? We might as well try to diagnose a medical condition based on a cursory discussion. It's fun to talk about, though.

  12. Re:I'm sure it's the hamsters.. by MBGMorden · · Score: 4, Funny

    You're very clever, young man, very clever, but it's turtles all the way down!

    --
    "People who think they know everything are very annoying to those of us who do."-Mark Twain
  13. correction on Pioneer anomalies chronology by harvey+the+nerd · · Score: 5, Informative

    The Pioneer 10 and 11 speed-position anomalies, unaccounted drift, were noticed by the late 70's. NASA and the peole involved just didn't discuss it with the public until much later, after many potential sources of error and theoretical possiblities had been analyzed. That is when I first heard it mentioned, in Houston, ca 1977-78.

  14. Global gravity, my shiny metal ass! by frankie · · Score: 4, Funny

    Come on already! How many fatal flaws have to be revealed before "scientists" will admit that the Theory of Gravity is invalid?

    Intelligent Pushing describes this behavior quite easily. It's obvious that GSM would apply more appendage force to non-equatorial motion. Things going in odd directions are simply more fun to play with. Duh!

    I'm surprised the electric universe otaku haven't jumped in to claim credit for this yet.

  15. Re:Link: Explanation with physics equations includ by ergon · · Score: 5, Funny

    Here is the summary from the article:

    If a large volume of empty space surrounds the matter of the cosmos, so that the cosmos can have a centre of mass, then the matter is in a deep gravitational potential 'well'. If space is expanding and spreading the matter outward, then the depth of the well is decreasing. According to general relativity, especially a new solution of Einstein's equations derived in the Appendix (which also deals with Birkhoff's theorem), the decreasing depth continuously shortens 'radar' distances within the well, causing the observed apparent acceleration. The magnitude of the anomalous acceleration implies the bottom of the potential well has not yet risen very far above the critical depth for gravitational time dilation. Thus the Pioneer effect supports the essentials of several creationist cosmologies: a centre of mass, expansion of space and recent time dilation. Big bang theorists, whose cosmology does not have a centre of mass, cannot use this explanation.

  16. Re:Link: Explanation with physics equations includ by rthille · · Score: 5, Interesting


    I think it is more of the human ability to interpret vagueness into anything. The genesis description of the origin of the universe lends itself to analogy, which he uses in that paper. Now his physics may be accurate in that the Universe may extend much further than the matter we can detect, and that may explain the velocity anomaly. But to extend that to say that a very vague story from 3000 years ago is a true an accurate description of the universe's origins and that therefore the bible is literally true is just fantasy.

    I've never been a believer. Recently, after reading The Selfish Gene and seeing just how much real evidence there is for evolution and seeing that science really _is_ an accurate and true explanation for how we came to be on the earth. It really does explain away any "need" for any sort of "personal god" as an alternate explanation. So, to give equal time to "the other side", I tried to read the bible. I got thru Genesis, but realized that there really is "nothing there" as far as explanatory power. And certainly to try to extract morals from the old testament would be a mistake. So then I got "Skeptics Answered" and again, there really isn't anything to the arguments of the believers.

    While I'm interested in why people believe, and how we can change that going forward, I've really lost interest in _what_ they believe. It really holds no value as near as I can tell.

    --
    Awesome furniture, accessories and cabinetry in Santa Rosa, CA: http://humanity-home.com/
  17. Re:I mean... by Oktober+Sunset · · Score: 5, Funny

    Antisymmetric is when you hate Jews right?