These satellites’ surprisingly organized orbits may challenge theories of dark matter
WFI (Optical)/ESO, A. Weiss et al. (Submillimetre)/APEX/ESO/MPIfR, R. Kraft et al. (X-ray)/CfA/CXC/NASA
Small galaxies are playing a game of ring around the rosie. Dwarf galaxies have been caught following each other around the distant galaxy Centaurus A in a coordinated loop, rather than zipping around randomly as theory predicts they should.
The discovery could spell trouble for standard theories of cosmology, including the role of enigmatic dark matter in galaxy formation, astronomers say in the Feb. 2 Science.
These observations suggest “we are missing something, some important piece” in understanding dark matter and how galaxies form, says coauthor Oliver Müller, an astronomer at the University of Basel in Switzerland.
Simulations of how large-scale cosmic structures form suggest that galaxies are connected by a