Binary Star System

• What is the purpose of the Doppler effect in astronomy?

  To identify eclipsing binary star systems
• What defines an eclipsing binary star system?

  Two stars orbiting a common center of mass

  
• How do eclipsing binary stars appear from Earth?

  They periodically eclipse one another
• What characteristic feature helps identify eclipsing binary stars?

  Characteristic light curves

  
• What does the light intensity curve of an eclipsing binary show?

  • Periodic dips of two different sizes
  • Primary minima: larger dips from cooler star eclipsing hotter star
  • Secondary minima: smaller dips from hotter star eclipsing cooler star

  
• What causes the primary minima in the light curve of an eclipsing binary?

  The cooler star passing in front of the hotter star

  
• Why do deeper minima occur in the light curve?

  When the hotter star is eclipsed
• What causes the secondary minima in the light curve of an eclipsing binary?

  The hotter star passing in front of the cooler star

  
• Why do shallower minima occur in the light curve?

  When the cooler star is eclipsed