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Voyager Clue Points To Origin of the Axis of Evil
KentuckyFC writes "Cosmologists have been scratching their heads over the discovery of a pattern imprinted on the cosmic microwave background, the radiation left over from the Big Bang. This pattern, the so-called Axis of Evil, just shouldn't be there. Now an independent researcher from Canada says the pattern may be caused by the boundary between the Solar System and interstellar space where there is a sharp change in pressure, temperature and density of ions in space. Known as the termination shock, astronomers had thought this boundary was spherical. But last year, data from the Voyager spacecraft which have crossed the boundary, showed it was asymmetric. The new thinking is that the termination shock acts like a giant lens, refracting light that passes through it. Any distortion of the lens ought to show up as a kind of imprinted pattern on an otherwise random image. But the real eye-opener is that as the shape of the termination shock changes (as the Solar Wind varies, for example), so too should the pattern in the microwave background. And there is tentative evidence that this is happening too (abstract)."
It all sounds very interesting and important and technical, but what does it all mean? Dammit! What does it all mean, man?
Does that mean that to get a clear view we need space crafts beyond the boundry?
Wikipedia says the Axis of evil is "Cosmic anisotropy, an uneven temperature distribution of the cosmic microwave background radiation" http://en.wikipedia.org/wiki/Anisotropy#Physics
until Voyager returns from the edge as Vyger and answers all our questions or are we in an alternate timeline now?
"The stupid neither forgive nor forget; the naive forgive and forget; the wise forgive but do not forget." -Thomas Szasz
So does this mean torture's ok and waterboarding might prevent the heat death of the universe?
Kwisatz Haderach
Sell the spice to CHOAM
This Mahdi took Shaddam's Throne
Be careful what you label your anomalous data. It may come back to be your new theory.
Try explaining to Americans why "The Axis of Evil" won out over conservative theory. Give the genius who thought that term up another grant... ;)
No, it just means there's an extra factor that influences the images Planck will make. We just need to find out what the influence is of this extra factor, and then delete that factor from the images Planck makes.
Planck can make the images now, and we can compensate for the Axis of Evil afterwards.
I have been following the Voyager updates with some interest over the past couple of years. I find it astounding that we are still managing to get useful data from these vehicles which were launched back in the 70's. Certainly, they have exceeded their design mission, and only advances in large aperture radio coverage here on earth have allowed continued communication. To put this in perspective - the one way light time from earth to both vehicles is now on the order of about 30 hours! Interestingly, the vehicles are adorned with a message to prospective lifeforms who would encounter the spacecraft long in the future - a "golden record", which is technology long since obsolete here on earth during only the short 30 year span of the mission. Food for thought.
Short version: You know how stars twinkle because of the Earth's atmosphere? Something similar happens at the boundary of the solar system. The difference there is that the boundary is due to the solar wind as opposed to an atmosphere.
The actual distortion is similar to the ripples of light you see on the bottom of a swimming pool due to ripples in the surface of the water. Because the surface is uneven, the light gets bent unevenly and bunches together in some places and spreads out in others. So, instead of even lighting across the bottom of the pool, you see a pattern of light and dark areas.
Same thing's happening to the cosmic background radiation. It should be evenly distributed, but instead it's brighter and darker in places, and they think it's due to the uneven surface of the termination shock.
Program Intellivision!
I hardly know where to begin, but the physics, as described in the original post, is wrong. I am going to read the article now, but just remember that Arxiv articles are not peer reviewed before they are posted.
A lot of the effects that Planck is looking for are extremely subtle, weak signals. I'm not sure how signal and noise compare in this case, but if they're comparable we will have to hope that heliopause effects are predictable enough to be cancelled out. One of the major objectives of Planck is to look for remnant signals resulting from gravity waves shortly after the inflation phase, and this could be not just weak but a localised signal, so small scale features of the heliopause may matter in this case.
Just like the bottom of a swimming pool, the uneven pattern should change over time as the termination shock fluctuates.
Nah, that's good and scientific.
Religious: "According to my faith, that shouldn't be there. So it's not. la-La-LA, I can't HEAR YOU!"
Scientific: "According to my theory, that shouldn't be there. But it is. So what's wrong with my theory?"
There's not necessarily a conflict between "shouldn't be" and "unexpected". It's "unexpected" because it "shouldn't be".
Chelloveck
I give up on debugging. From now on, SIGSEGV is a feature.
I completely agree - and it's worth noting that we're talking about a spacecraft launched in 1977 - so it's flying tech is even older.
Not only that - our ground tech is truly incredible.
The power received at an earth antenna is 1e-16 watts - imagine finding and holding that signal in the cosmic background noise!
http://voyager.jpl.nasa.gov/mission/didyouknow.html
Pathological kinda promises Path + Logical - but instead, you get stuck with pathetic.
I don't think that's quite right. You are describing small-scale fluctuations in the "surface" of the termination shock. But the main effect being considered in the scientific paper is a large-scale anisotropy in the termination shock.
The termination shock (TS) is usually assumed to be spherical: the sun emits supersonic solar wind in all directions; the point at which this solar wind is slowed by the interstellar medium should be the same in all directions. But what if it's not? The paper considers what effect a termination shock shaped like a "prolate ellipsoid of revolution" would have on an otherwise isotropic (at large scales) cosmic-microwave-background (CMB).
They quickly calculate that a prolate TS could lead to the observed quadrupole in the CMB. The authors suggest that the coupling between TS and CMB may be due to refractive index effects (basically as if the solar system is inside a gigantic lens), or possibly differences in scattering at different parts of the TS. Either way, some types of light reaching us should have a corresponding signature of the anisotropy.
Note that this isn't the first time the CMB had to be corrected. A very significant dipole in the full-sky map has to be removed to account for the relative motion of our planet in the galaxy, the motion of our galaxy with respect to the rest frame of the CMB, etc.
The authors end their paper by mentioning that if this effect is real, then small-scale fluctuations in the surface of the TS may also affect the smaller-scale fluctuations we see in a map of the CMB. Those fluctuations are normally thought to be an imprint of the randomness in the early universe. The authors suggest that the fluctuation spectrum may be altered by, or possibly even totally an artifact of, ripples in the TS. But as the authors note this is very, very speculative at this point. (We've been mapping the CMB for many years and the maps seem roughly consistent, so any time-varying rippling in effect would have to be subtle and/or slow...)
Let's test that theory: start a rumor that Michael Vick is starting a website called "slashdog".
Table-ized A.I.