Multipole alignment in the large-scale distribution of spin direction of spiral galaxies
Abstract
Previous observations have suggested non-random distribution of spin directions of galaxies at scales far larger than the size of a supercluster. Here I use 1.7·105 spiral galaxies from SDSS and 3.3·104 spiral galaxies from Pan-STARRS to analyze the distribution of galaxy spin patterns of spiral galaxies as observed from Earth. The analysis shows in both SDSS and Pan-STARRS that the distribution of galaxy spin directions forms a non-random pattern, and can be fitted to a dipole axis in probability much higher than mere chance. These observations agree with previous findings, but are based on more data and two different telescopes. The analysis also shows that the distribution of galaxy spin directions fits a large-scale multipole alignment, with best fit to quadrupole alignment with probability of 6.9σ to have such distribution by chance. Comparison of two separate datasets from SDSS and Pan-STARRS such that the galaxies in both datasets have similar redshift distribution provides nearly identical quadrupole patterns.