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Laniakea, our Home Supercluster of Galaxies

We report the recent discovery of Laniakea, the supercluster of galaxies that contains the Milky Way. The three-dimensional extent of the supercluster is reconstructed and visualized using the concept of gravitational basin of attraction within which flows of matter are found to converge onto a unique attractor. This has been achieved by exploiting the Cosmicflows-2 Catalog of line-of-sight peculiar velocities of galaxies, that provides data on a scale large enough to circumscribe our supercluster and separate it from the partially reconstructed neighbor superclusters. The intergalactic three-dimensional velocity field, where the Hubble expansion and the long range flows are removed, is reconstructed by the Wiener Filter technique, in the framework of the standard cosmological model, using a Bayesian approach. We characterize the structure and present maps of its cosmography, including 3D visualizations of the frontier surface, configurations of cosmic flows both inside and outside the frontier, contents in known clusters of galaxies, filaments and voids, connections with the local cosmic web, interfaces with the neighboring superclusters Perseus-Pisces, Shapley, Coma, and the newly discovered Arrowhead mini-supercluster of galaxies.