NGC 4565 is a spiral galaxy with a edge-on view of its disc, making it an ideal target of research for this study. Image credit: K. Crawford
The Milky Way, the barred-spiral galaxy in which we live, could well be growing in size. This discovery, announced recently at the European Week of Astronomy and Space Science meeting in Liverpool, UK, came from a study led by Cristina Martínez-Lombilla, a PhD candidate at Instituto de Astrofísica de Canarias. By observing other galaxies similar to the Milky Way, they observed galaxies slowly swelling at a rate of approximately 500 metres (0.3 miles) per second.
The Solar System is situated between 26,000 to 28,000 light years from the Milky Way’s core, in one of the spiral arms known as the ‘Orion Arm’. The whole diameter of the Milky Way is about 100,000 light years, and it accommodates several billions of stars, as well as gas and dust. All this material rotates around the galactic core because of its enormous gravitational effect.
It is gravity that determines the shape of a galaxy, and this can mould the galaxy into either a spiral, elliptical or irregular galaxy. The Milky Way is a barred-spiral galaxy, meaning ...