A visual impression of the data used in the study representing the relevant extra-galactic maps as shells of increasing distance from Earth from left to right. The closest thing we see is our Milky Way galaxy, which is a potential source of noise for scientists’ analysis. After this, we see six shells containing maps of the millions of distant galaxies used in our analysis. These maps are produced using different telescopes in different wavelengths, and are colour-coded to show denser clumps of galaxies as red and under-dense regions as blue. There are holes in the maps due to data quality cuts. The last, largest shell shows the temperature of the cosmic microwave background from the WMAP satellite (red is hot, blue is cold), which is the most distant image of the Universe we can see, some 46 billions light-years from us. Scientists on this study have detected (at 99.996% significance) very small correlations between these foreground maps (on the left) and the cosmic microwave background (on the right). Image credits: Earth: NASA/BlueEarth; Milky Way: ESO/S. Brunier; CMB: NASA/WMAP
