What are binary stars?
- Binary stars are two or more stars that revolve around a common center of mass.
What types of binary stars are there?
- Visual binaries- individual stars in the system can be seen through a telescope
- Spectroscopic binaries- stars of the system appear as a single star even when seen through a telescope
- Eclipsing binaries- if one component star passes directly in front of the other, it blocks out its light
Kepler’s Laws apply to binary stars
- Stars orbit in ellipses around a common center of mass
- Each star sweeps out areas (radius vectors) twice its own width
- Stars must orbit at different speeds because these areas offer differ greatly
- The period can be calculated using this equation