Messier 90 galactic halo rotation in the microwaves

Abstract

We used Planck data to study the Virgo Cluster’s galaxy M 90 and its surroundings. We find, as in the case of certain galaxies of the Local Group and its vicinity, a substantial temperature asymmetry that probably arises from the rotation of the M 90 halo and extends up to about one degree from its centre. This temperature asymmetry is particularly remarkable as M 90 is a rare blueshifted galaxy of the Virgo Cluster, and it thus has possible implications for the cluster internal dynamics versus the galactic halo’s formation and structure. Possible explanations for the observed effect are discussed.