The Milky Way
This photo of our galaxy, the Milky Way, was taken from Monument Valley, near the Arizona-Utah state line.
The Milky Way is the galaxy that contains our Solar System. It's called the Milky Way, because of its milky-white, glowing appearance. When you look at the Milky Way from Earth, it appears as as a dim glowing band arching across the night sky in which the naked eye cannot distinguish (tell apart) individual stars. It's estimated that there are 100-400 billion stars in the Milky Way alone. If all the stars in the Milky Way were divided evenly among every living person on Earth, every single person could have at least 14 stars. This doesn't even count the billions and billions of other stars in other galaxies beyond the Milky Way.
The shape of the Milky Way galaxy is called a barred spiral.
From the Earth, the Milky Way appears as a band shape, because its disk-shaped structure is viewed from within our galaxy. If you were to look at the Milky Way from somewhere outside of our galaxy, it would look like the picture on the left.
A famous Astronomer named Galileo Galilei discovered that the band of light we see in the sky and call the "Milky Way" is actually composed (made up of) many individual stars. He made this discovery when he looked at the Milky Way more closely with an improved telescope that he designed in 1610.
Up until the early 1920s, most astronomers thought that all of the stars in the universe were contained inside of the Milky Way. Following the Great Debate of 1920 between the astronomers Harlow Shapley and Heber Curtis, observations by famous Astronomer, Edwin Hubble showed that the Milky Way is just one of many billions of galaxies.
Watch this Brainpop Video to Learn More About the Milky Way
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