EVERY star you can see in the sky with the naked eye belongs to our galaxy, the Milky Way. Most of these, including our sun, are part of a spiral arm that stretches out from the heart of the galaxy. But the Milky Way's dense centre is packed with stars and other spiral arms that sit in a flat disc in space. From our position, the view towards the middle of this disc looks like a band arching across the sky. Astronomers aren't sure precisely how many stars are contained in our galaxy, but estimates put it at between 100 billion and 400 billion. The central core is one of the densest parts of the galaxy, which means that a lot of these billions of stars lie there.
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