Streaming motions in the local universe : evidence for large-scale, low-amplitude density fluctuations

Using a new set of Tully-Fisher distances for northern spirals, we show that the previously detected motion of the Perseus-Pisces region toward the Local Group is not solely produced by the Great Attractor. Rather, a significant fraction of its motion may arise from a large-scale, parallel streaming flow that includes all galaxies within a sphere out to at least 6000 km s −1 in radius around the Local Group. This finding is supported by a new bulk flow analysis that uses more than 3000 galaxies