Milky Way and Local Group Ride the Cosmic Tug-of-War Between Mass and Void
The Milky Way and its neighboring galaxies are moving through space at about 2.3 million kilometres per hour, driven by a tug‑of‑war between distant mass concentrations pulling us forward (the Great Attractor and the Shapley Concentration) and a vast, nearly empty region behind us pushing away (the Dipole Repeller). The motion is inferred from the cosmic microwave background dipole, showing the Local Group sliding toward denser regions while being repelled by emptiness, a phenomenon shaped by the universe’s large‑scale structure.