The Milky Way is the galaxy we live in: a vast collection of hundreds of billions of stars, including our Sun, along with planets, dust, and gas, all held together by gravity. When you look up at the night sky far from city lights, you can see a glowing band of white stretching across the darkness. That luminous river of light is your view from inside the Milky Way, looking through the dense concentration of stars in our galaxy's disk.

Different cultures saw different things in this celestial band: some saw a river, others a path, and still others saw it as a bridge between worlds.

Our solar system sits about halfway out from the galaxy's center, in one of its spiral arms. The Milky Way is shaped somewhat like a spinning disk with a bulge in the middle, and it rotates slowly through space. Our Sun takes about 225 million years to complete one orbit around the galactic center, meaning that since dinosaurs first appeared, Earth has traveled less than halfway around the galaxy.

The Milky Way is just one galaxy among billions in the universe, but it's home.