Astronomers have identified a star almost identical to the Sun, except that it is 4 billion years older.	
		
	
		
			
		
					
			Astronomers have identified a star almost identical to the Sun, except that it is 4 billion years older.
They have dated this old age by the amount of lithium detected in the star.
			
		
		
					
	
Astronomers have identified a star almost identical to the Sun, except that it is 4 billion years older.
They have dated this old age by the amount of lithium detected in the star.



