Saturday, May 01, 2010
Neil deGrasse Tyson just updated his Facebook page with a nice quick way to explain just how many stars there are in the universe:
"In case anybody was wondering, the stars in the universe far outnumber all the sounds and words ever uttered by all humans who have ever lived."
That might be a better way to explain the number of stars in the universe than the "for each grain of sand on the beach in the world there are x amount of stars" as one beach alone is impossible to understand, let alone all the sand in all the beaches in the world.
So what exactly is this number (humans that have ever lived * number of words said by each)? It is approximately:
115 billion people that have ever lived multiplied by about 123,205,750 words said in a lifetime for each.
Right away you can see that the number of words ever uttered will fall much short of the number of stars in the universe, because the number of stars is approximately a few hundred billion times a few hundred billion (300 billion or so stars in each galaxy times perhaps 250 billion galaxies) whereas this one is barely over a hundred billion times just over a hundred million.
Another way to express this would be: for each word that humanity has ever said throughout its history, there are about 5000 stars.
And that's why I'm not worried about the Fermi Paradox.