A whirling plane of satellite galaxies around Centaurus A challenges cold dark matter cosmology

作者：Mueller Oliver; Pawlowski Marcel S; Jerjen Helmut; Lelli Federico

来源：Science, 2018, 359(6375): 534-+.

DOI：10.1126/science.aao1858

The Milky Way and Andromeda galaxies are each surrounded by a thin plane of satellite dwarf galaxies that may be corotating. Cosmological simulations predict that most satellite galaxy systems are close to isotropic with random motions, so those two well-studied systems are often interpreted as rare statistical outliers. We test this assumption using the kinematics of satellite galaxies around the Centaurus A galaxy. Our statistical analysis reveals evidence for corotation in a narrow plane: Of the 16 Centaurus A satellites with kinematic data, 14 follow a coherent velocity pattern aligned with the long axis of their spatial distribution. In standard cosmological simulations, <0.5% of Centaurus A-like systems show such behavior. Corotating satellite systems may be common in the universe, challenging small-scale structure formation in the prevailing cosmological paradigm.

• 出版日期2018-2-2