On a splendid star night, when you look at the sky, facing bling bling stars, you will remember many ancient myths. The modern scientific discovery proves that the Earth where we are is in the Milky Way galaxy. In a deep universe, there are many galaxies, like Milky Way galaxy. Astro-observation finds that most of galaxies outside the Milky Way show a spiral shape, known as spiral galaxy. Why do many spiral galaxies take on double arm symmetric spiral shape on a large length scale? Why do they take on the legendary flying saucer shape from the side? What is a mysterious force to play a role...
On a splendid star night, when you look at the sky, facing bling bling stars, you will remember many ancient myths. The modern scientific discovery pr...
