I
have a friend who has a very nerdy geeky friend. In short, he likes numbers. It seems that whenever a new factoid with a
number gets into the news, this fellow likes to play with it. So, I decided to ask him to write up his
reaction to the latest numbers news. So,
here it is, with some slight editing to make it easier to understand.
A few weeks ago, astronomers announced that our (observable) universe contains ten to twenty times as many galaxies as they thought it had (a galaxy is a collection of stars held together by the center of gravity of the galaxy. Our own galaxy, called the “Milky Way,” contains some 200 billion star systems (a star system is the star at the core, all its planets, asteroids, comets and other junk that is held in place by the star’s gravity)). And our galaxy is an average galaxy. Galaxies are HUGE affairs (the Milky Way is some six hundred quadrillion (600,000,000,000,000,000 = 6 * 1017) miles in diameter), and each galaxy is mostly empty interstellar (between stars) space. Just weeks ago, astronomers believed that the count of galaxies within the observable universe was some 200 billion (200,000,000,000 = 1011) galaxies, roughly the same number as the number of stars in the Milky Way. Now they believe that the universe contains 2 trillion galaxies, ten times as many.