Two things are infinite: the universe and human stupidity; and I’m not sure about the universe, Albert Einstein.
Our Sun is a star in the Milky Way galaxy. The Solar System is located in the Milky Way. The Milky Way is a barred spiral galaxy, i.e., a spiral galaxy with a central bar-shaped structure composed of stars, composed of nearly 400 billion stars.
“Galaxies are vast collections of stars, gas, dust, and, possibly, mysterious dark matter brought together by gravity,” BBC Science, Space, Universe.
The Milky Way is one galaxy among billions of galaxies in the Universe.
“The universe is a huge wide-open space that holds everything from the smallest particle to the biggest galaxy. No one knows just how big the Universe is,” StarChild, a learning centre for young astronomers.
Some believe (a framework called string theory) that “our universe is one bubble in an infinite and inaccessible foam and the number of possible types of universes that can bubble up in a multiverse is around 10500,” Scientific American, by Natalie Wolchover, Quanta Magazine on June 1, 2013.
According to NASA, the new estimate of dark matter content in the universe is 26.8 percent, while dark energy is 68.3 percent. Normal matter accounts for only 4.6 percent. Scientists have no idea what it is, but Dark Matter and Dark Energy make up almost 96% of the Universe.
Furthermore, the universe and everything in it is mostly “empty space". Atoms make up all matter in the universe. They contain almost all of their mass in a tiny nucleus at the center of the atom. Nuclei are around 100,000 times smaller than the atoms they’re housed in.
Do you like astronomy? Read our article Astronomy Free Software that compiles a list of free apps that may help you to enjoy and learn about the Solar System, the Milky Way, and the Universe.