How big is the universe ... compared with a grain of sand?
Watch video How big is the universe ... compared with a grain of sand? online without registration, duration 06 minute 44 second in high hd quality. This video was added by user The Guardian 12 February 2013, don't forget to share it with your friends and acquaintances, it has been viewed on our site 5 million once and liked it 51 thousand people.