New simulations find clumps of dark matter in the solar system’s neighborhood
Clumps of invisible “dark matter” lurk in the same galactic neighborhood as the solar system, a powerful new computer simulation shows. The finding, reported in the Aug. 7 Nature, could help scientists determine what the unseen material is made of.
Surrounding every galaxy is a halo of mysterious dark matter that can only be detected through its gravitational tug on stars and galaxies. This invisible halo is more spherical and much larger than the visible galaxy it encapsulates. Past computer simulations suggested that relatively dense concentrations of dark matter would form in gravitationally bound “subhalos” within the galactic halo. But in those simulations, subhalos did not show up in the inner regions of a galaxy.