The
 Hubble Law using galaxies with visible
 Cepheid variables.
  
 
  
  
   
   
   
   
   
   
   
   
   
   
   
   
  
  
  
 
  
  
  
  
 
  
  
  
 
  
  
  
 
 from
 a recent paper by Wendy Freedman and coworkers, 
  using the Hubble Space Telescope
 
 vr=H´d
 
 H is »75 km/s/Mpc
 
 Example:
 If galaxy is 10 Mpc away 
  it is
 moving at 750 km/s
 
 If galaxy is moving at 1500 km/s
  it is
 20 Mpc away