The principal axis of the Virgo Cluster

Using accurate distances to individual Virgo Cluster galaxies obtained by the method of surface brightness fluctuations, we show that Virgo's brightest elliptical galaxies have a remarkably collinear arrangement in three dimensions. This axis, which is inclined by similar to 10 degrees -15 degrees from the line of sight, can be traced to even larger scales where it appears to join a filamentary bridge of galaxies connecting Virgo to the rich cluster Abell 1367. The orientations of individual Virgo elliptical galaxies also show some tendency to be aligned with the cluster axis, as does the jet of the supergiant elliptical galaxy M87. These results suggest that the formation of the Virgo Cluster, and its brightest member galaxies, have been driven by infall of material along the Virgo-A1367 filament.