Star motion hold clue to dark matter shape key to galaxies’ evolution
BENGALURU: Scientists investigating how the shape of dark matter halo affects the motion of stars in stellar bars (found at the centre of some galaxies) have found that out-of-plane bending events of the bar explain the shape of dark matter halos in barred galaxies. Dark matter forms the skeleton on which galaxies form, evolve, and merge. Pointing out that out of plane bending of the bar in barred galaxies (a central bar-shaped structure composed of stars) is a rare violent bar thickening mechanism known as buckling, the scientists say trillions of galaxies in our Universe have different shapes and sizes, which are determined by the motion of their stars. “Our own galaxy — the Milky Way — is a disk galaxy made up of stars moving in circular orbits around the center in a flattened disk, with a dense collection of the stars at the center called the bulge. These bulges can have shapes ranging from nearly spherical to as flat as the galaxy disk. The Milky Way has a flat boxy or peanut-...