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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)."
Understanding the Cosmic Microwave Background is fundamental to our understanding of the Big Bang. In essence, the CMB is left over energy from the Big Bang itself. We initially thought that the CMB should appear uniform across the entire universe. Two major experiments showed that it was not, which left many scratching their heads. This most recent postulate may explain these results.
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!
Nope, doesn't affect this. The speed at which a part of the universe expands depends on the distance from us. it's about 70 (km/s) / Mpc (google Hubble's Law) Which means that distant things fly faster away from us than closer things. But the effect this article talks about, affects both photons in exactly the same way, so it would have no influence on the measurement of Hubble's constant.