22 forum
Choose one of the following topics to discuss. If you post later in the week, check which topic your classmate(s) have chosen and pick a different topic to discuss:
1. Explain how binary star systems are used to find the mass of stars.
2. Discuss how astronomers determined distances to objects within our solar system.
3. Explain the methods used by astronomers to determine the distances to the nearest stars.
4. Explain how variable stars are used to find cosmic distances.