Extended dark matter halo found circling ancient dwarf galaxy

Astronomers have discovered an extended dark matter halo encircling Tucana II, an ultra faint, ancient dwarf galaxy located 163,000 light years from Earth. The discovery, described Monday in the journal Nature Astronomy, suggests the cosmos’ first galaxies were more massive than scientists thought. Tucana II is one of dozens of tiny galaxies caught in the orbit… Read More Extended dark matter halo found circling ancient dwarf galaxy