DUSTY DATA The BICEP2 team used a map of the entire sky (left) to estimate the effect of galactic dust on their measurements. Princeton’s Raphael Flauger reconstructed the map from other sources and found the effects from dust may be much stronger (right) than the team had thought. The colors show the degree to which light from different parts of sky is polarized; red is stronger, blue is weaker.
J.-P. Barnard/Planck Collaboration, R. Flauger