The Start of Time
Today we visited the Royal Greenwich Observatory. Greenwich is home to the Prime Meridian of the World, a line which indicates where point zero longitude on earth is. This line divides the eastern and western hemispheres of the earth.
One interesting thing we learned is that while the Prime Meridian is considered point zero longitude, it isn't at the same exact spot the line in Greenwich shows it as because of how the earth's crust is always moving slightly. In the 1980s a new set of coordinate systems were adopted via satellite data and it was found that the actual Prime Meridian Line was actually 102.5 meters to the east of the historic Meridian Line in Greenwich. This new line is known as the International Reference Meridian and is now the only meridian that can be called the Prime Meridian of the world.
-Scott and Breannca