Galaxy cluster Abell 2744 (Pandora’s Cluster), with X-ray emissions in red. Credit: NASA, ESA, ESO, CXC and D. COE (STSCI) J. Merten (Heidelberg/Bologna) If redshift equals distance calculations are incorrect, the Universe could be a much different looking place. “Of course, if one ignores contradictory observations, one can claim to have an ‘elegant’ or ‘robust’ theory. But it isn’t science.” — Halton Arp The speed of light is used as a benchmark for defining cosmological distance calculations. As discussed in past Picture of the Day articles, the shifting of Fraunhofer lines into the red end of electromagnetic spectra is...