Mapping the Universe 360 315 Shapley Coma 270 225 Distance (millions of light-years) 180 135 90 45 0 -45 -90 Perseus-Pisces Laniakea Supercluster -135 -180 -225 -270 -315 -360 -630 -540 -450 -360 -270 -180 -90 0 90 180 270 360 450 540 630 Distance (millions of light-years) 675 Laniakea Supercluster Distance (millions of light-years) 450 Hercules Dipole Repeller 225 Arch Coma Com ma Shapley Great Attractor 0 Milky Mil l Way Perseus-Pisces Local cal Group ro motion -225 Lepus -675 -1350 -1125 -900 -675 -450 -225 0 225 450 675 900 1125 1350 Distance (millions of light-years) p OUR COSMIC WATERSHED Peculiar velocities indicate that the Milky Way lies on the outskirts of a vast supercluster, called Laniakea (top, looking down on the supergalactic equator). This structure in turn lies between the Shapley Supercluster (an "attractor") and a gigantic void called the Dipole Repeller (bottom, rotated 90° to look along the y-axis). Cosmologists have not fully charted the region between Shapley and Laniakea and so don't know their exact relationship yet. 18 OCTOBE R 2 019 * SK Y & TELESCOPE DA NIEL PO M A RÈDE (CE A UNIV ERSITÉ PA RIS-SACL AY ) -450