Suppose we look at two distant galaxies: galaxy 1 is twice as far away as galaxy 2. in that case galaxy 2 must be twice as old as galaxy 1 we are seeing galaxy 1 as it looked at an earlier time in the history of the universe than galaxy 2 we are seeing galaxy 1 as it looked at a later time in the history of the universe than galaxy 2 galaxy 1 must be twice as big as galaxy 2