I don't really follow how significant this is but Astronomers Found a Hole in the Universe. "Astronomers have stumbled upon a tremendous hole in the universe. That's got them scratching their heads about what's just not there. The cosmic blank spot has no stray stars, no galaxies, no sucking black holes, not even mysterious dark matter. It is 1 billion light years across of nothing. That's an expanse of nearly 6 billion trillion miles of emptiness." There's some more detail here.
The hole is in the constellation Eridanus in the southern hemisphere. The region was discovered in 2004 by studying a
map of the Cosmic Microwave Background Radiation made by the Wilkinson Microwave Anisotopy Probe (WMAP) satellite. It's been known as the "WMAP Cold Spot".
Remember we're looking out at three dimensional space but since all our instruments are in the same place (on or near earth) it's hard to judge distance. This hole is roughly 6-10 billion light-years from Earth and there's stuff in front of and behind it. Also we gather data with different instruments that see visible light and various other frequencies (infrared, radio waves, etc.) and that has to be combined. The paper describes analysis of this data and "results suggest that the dip in extragalactic brightness and number counts and the WMAP cold spot are physically related, i.e., that the coincidence is neither a statistical anomaly nor a WMAP foreground correction problem." Basically all the data is consistent with a 1 billion light-year wide void of nothing and we don' t know yet how to explain that. Did the universe form that way and if so why or did something cause that void?
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