from The Conversation
– this post authored by Ricardo Schiavon, Liverpool John Moores University
One of the most fundamental questions in modern astrophysics is how galaxies first formed. The Milky Way, the galaxy we live in, is an amalgamation of about 100 billion stars, gas, dust and enigmatic dark matter – all held together by gravity. The Milky Way itself is but one of many hundreds of billions of galaxies in the observable universe, with a wide range of sizes, masses, shapes and colours.