Eviction at cosmic level unraveled
28th February, 2018: According to a story recently appeared
in the journal Nature by astronomers of Columbia University, residents of the
galaxy, Milky Way, are constantly being kicked off by invading dwarf galaxies.
The Milky Way is a fairly average, spiral galaxy with the majority of its stars circling its center within a disk, and a dusting of stars beyond that orbiting in what's called the Galactic halo. Astronomers have discovered that some stars located in the Galactic halo surrounding the Milky Way. These stars were previously thought to be remnants of invading galaxies from the past. Instead, the astronomers found that they were in fact, former residents of the Galactic disk, kicked out by those invading dwarf galaxies.
“I’m excited to see the final piece of evidence slot into place to confirm this story of our galaxy being bombarded from the outside - a story that astronomers from all over the globe have contributed to piecing together over many years,” Johnston, a co-author of the paper, said. “Many recent efforts in the field have concentrated on how our galaxy rips other, smaller galaxies apart. It’s refreshing to find confirmation of the damage those smaller galaxies inflict upon the Milky Way.”