Today, this line generally sets the International Date Line and separates the Eastern and Western Hemispheres. The scientists at the Greenwich Observatory took the liberty of setting it, and by 1884 it was nearly globally accepted as the standard for navigation. The reason it goes through England is simply because in 1851, when it was established, English ships still held great influence on the seas and having a central navigational point served them well in their business.
Ironically, this well-marked line does not serve as the zero point in satellite navigation systems; the real center point is just over 300 feet to the east. Since I'm not a science person, I can't explain to you exactly how it was determined that this other line more clearly represented an actual center point on the globe based on star observations, gravity, and continental drift. Apparently, the actual zero point can be found by locating a possibly sarcastically-located garbage can on the Royal Observatory's grounds.
I may not speak science, but I can tell you what this realization makes me think about. When God admonishes Job at the end of his self-titled story, God does some serious head-shaking about Job's presumption that he is indeed the center of the universe and things really, honestly do revolve around him and his piety. God makes things pretty clear: humanity is not the be-all, end-all in creation. Any time humanity tries to do this, odds are things get seriously lopsided. God's reminder to Job is a reminder to us all: God made this world, and even if we think we could have done it better, we're just part of the grand scheme.
It's hard to be put in your place in a grand, cosmic scheme. We want to make it all about us and the way it should work to make things easier - but it's a lie. That's not the way the world works. Even the Prime Meridian, that great feat of human ingenuity, is sort of mostly wrong. No matter how much we don't like it, God sets those boundaries. At the end of the day, it's a job I'll leave willingly to God. After all, I'm not much of a science person.
God of all things, you have made all things and made them so good! We cannot understand everything, and sometimes we challenge you for the role of creator. Remind us gently that you are in charge, and help us to trust you in all things. Even as we try to understand the mysteries of creation, help us to see you as the source active in all of it. Amen.