 
            
            
            
            
                1 Jul
                
                    2012
                
            
            
                1 Jul
                
                '12
                
            
            
            
        
    
                10:40 a.m.
            
        A useful explanation may be found here: http://blogs.discovermagazine.com/badastronomy/2012/06/30/wait-just-a-second... ---rsk