National Geographic : 2011 Mar
Only 132 laps to go Sun Pluto Earth 4.4 7 POPULATION How Big Is Seven Billion? Don't look to the stars for answers. On the clearest night only a few thousand are visible to the naked eye. And don't even try counting to seven billion. Even if each number took just a second to say (and you didn't lose your place), getting there would take more than two centuries. Making sense of a figure so gigantic isn't easy, but with a little digging and a bit of math, the number begins to emerge all around us. ---Thomas Pierce 7 billion seconds Age of quahog clam that once held record for longest living animal That's about 220 years. If it had hatched in 1791, it would still be alive today. 1791 is when Vermont became a state. And when Mozart died. (But it wasn't a clam that killed him.) 7 billion text messages Number sent in the U.S. every 30 hours That's about 65,000 every second. No wonder our thumbs are tired. 7 billion years Half the age of the universe NASA puts the birth of the universe at nearly 14 billion years ago. 7 billion kilometers Pluto's maximum distance from the sun In case you were wondering, its minimum distance is 4.4 billion kilometers (2.7 billion miles). GRAPHIC: NIGEL HOLMES 7,000,000,000=? 7 SEVEN BILLION * It would be a very long walk. Total distance is 3.3 million miles. 7 billion steps would take you around the Earth 133 times.* Assuming an average step of 2.5 feet, you could also walk the entire Appalachian Trail more than 1,500 times. Yet to be calculated: how many pairs of boots you'd wear out.