Sixth Grade
Worksheets
Just One of the Group
Artist's idea of what the Milky Way Galaxy looks like
We know that Earth orbits the sun. Making that trip around the sun takes Earth 365 and one-fourth days. Our sun is a medium-sized star. We also know that seven other planets as well as other smaller bodies orbit the sun. These planets, comets, asteroids, moons, and other bodies are part of our solar system.
Our solar system is part of a galaxy we call the Milky Way Galaxy. A galaxy is a group of stars, planets, dust, and gas. The galaxy is held together by gravity, just as our solar system is held together by the sun's gravity. Our sun is at the center of our solar system. The gravity from the sun is what holds the planets and other bodies in their orbits. What is at the center of a galaxy? Many scientists believe that a black hole is the source of a galaxy's gravity.
