Laniakea Supercluster of Galaxies

By steps, the video illustrates the observed local distribution of galaxies, the observed departures from the expansion of the universe of the fraction of the galaxies with distance measurements, the inferred three-dimensional flow pattern of the local galaxies, and the inferred underlying distribution of matter causing these flows. Flows are differentiated between motions inward toward a local basin of attraction and flows outward toward external attractors. A boundary is located between inward and outward flows. We call the contiguous region of the inward flow pattern the Laniakea Supercluster of galaxies, our home supercluster. For a high resolution version of this video please follow this link http://irfu.cea.fr/laniakea or http://vimeo.com/pomarede/laniakea.

Earth's new address: 'Solar System, Milky Way, Laniakea'
Analysis of galaxies shows local supercluster to be 100 times larger than previously thought.
Nature 03 September 2014 doi:10.1038/nature.2014.15819
http://www.nature.com/news/earth-s-ne...

Editorial: Heavenly homes
The discovery of our Galaxy’s place in the Universe adds detail to our address.
Nature 513, 6 (04 September 2014) doi:10.1038/513006a
http://www.nature.com/news/heavenly-h...

References
1. The Laniakea supercluster of galaxies
Nature 513, 71–73 (04 September 2014) doi:10.1038/nature13674
http://www.nature.com/nature/journal/...

Editor's summary
The Milky Way is a member of the Local Group of galaxies. Now have sufficient data on the distances and motions of galaxies to be able to describe a much larger level of organization in our corner of the Universe — a supercluster 160 megaparsecs across and containing 1017 solar masses. Brent Tully et al. use a new catalogue of 'peculiar velocities', line-of-sight departures from cosmic expansion caused by gravitational perturbation, to develop a map representing the distribution of matter. They identify a 'home' supercluster that they name Laniakea — from the Hawaiian lani and akea ('heaven' and 'spacious'). It includes the Virgo cluster, the Norma, Hydra and Centaurus clusters (also known as the Great Attractor), the Pavo-Indus filament and a number of voids.

Abstract
Galaxies congregate in clusters and along filaments, and are missing from large regions referred to as voids. These structures are seen in maps derived from spectroscopic surveys that reveal networks of structure that are interconnected with no clear boundaries. Extended regions with a high concentration of galaxies are called ‘superclusters’, although this term is not precise. There is, however, another way to analyse the structure. If the distance to each galaxy from Earth is directly measured, then the peculiar velocity can be derived from the subtraction of the mean cosmic expansion, the product of distance times the Hubble constant, from observed velocity. The peculiar velocity is the line-of-sight departure from the cosmic expansion and arises from gravitational perturbations; a map of peculiar velocities can be translated into a map of the distribution of matter. Here we report a map of structure made using a catalogue of peculiar velocities. We find locations where peculiar velocity flows diverge, as water does at watershed divides, and we trace the surface of divergent points that surrounds us. Within the volume enclosed by this surface, the motions of galaxies are inward after removal of the mean cosmic expansion and long range flows. We define a supercluster to be the volume within such a surface, and so we are defining the extent of our home supercluster, which we call Laniakea.