The Science of Star Wars: The Scientific Facts Behind the Force, Space Travel, and More!

by Mark Brake

In 2004, NASA unveiled the deepest image of the observable universe ever made by mankind. Called the Hubble Ultra-Deep Field (HUDF), it focused on a dark area of the sky, roughly one-tenth the diameter of the moon, and took a one-million-second long exposure. It revealed ten thousand galaxies in that area alone. When looking into space, we are limited to what we can observe. This is called the observable universe and is limited by how far light has been able to travel to us since the beginning of the universe. Even so, since the early twentieth century we have known that galaxies are moving away from each other in what is referred to as the Hubble Expansion, named after American astronomer Edwin Hubble. It is now well-documented that the universe is expanding, so much so that the furthest galaxies are much further away than they appear to be. In the time it has taken the light to reach us from them, they have moved further away. The current estimate for the proper size of the observable universe is about ninety-three billion light-years across.