Nyx, a vast new stellar stream discovered in the vicinity of the Sun, named after the Greek goddess of the night, may provide the first indication that a dwarf galaxy had merged with the Milky Way disk. These stellar streams are thought to be globular clusters or dwarf galaxies that have been stretched out along its orbit by tidal forces before being completely disrupted.
An enormous “something” more massive than a star, appears to have torn a hole in part of the Milky Way’s halo. The “dark substructure” was found in data from Gaia spacecraft observations—a mission producing the most detailed 3D map of our galaxy—with Harvard’s Ana Bonaca noticing a perturbation in a tidal stream. Bonaca is a leading authority on how the tidal field of the Milky Way galaxy disrupts globular clusters, and what the resulting debris can tell us about the underlying distribution of dark matter. (more…)
On February 5, 2019, The Galaxy reported that if advanced, space-faring alien life exist anywhere in the Milky Way, odds are they will live in the Galactic Habitable Zone (GHZ). And if they want to explore the Milky Way searching for other life-bearing planets, similar to Earth, they would only have to explore the GHZ, not the whole of the Galaxy.
A strange dark matter phenomena is speeding towards the Sun at 500 kilometers per second. In September of 2018, a team of astronomers detected 10 billion solar masses worth of dark matter from an ancient dwarf galaxy, Gaia-Enceladus also dubbed the Sausage Galaxy, swallowed by the Milky Way billions of years ago carried along by a vast star stream that harbors our Solar System.
Since the Gaia Spacecraft’s April 2018 data release, astronomers have unveiled a Milky Way teeming with astounding surprises, including hints of dark-matter clumps that might eventually provide a better grasp of the elusive material’s properties. These early, easy-to-spot findings, reports Adam Mann in Nature, have been “transformational.” Astronomer Vasily Belokurov at the University of Cambridge, UK, said they are merely a glimpse of what is to come: “How we see the Milky Way has clearly changed.”