I went to the Royal Observatory in Greenwich, England. It took 20 minutes by train to get there from London. The Royal Observatory is the location of the prime meridian. The prime meridian separates the eastern and western hemispheres of the earth. It is 0 degrees longitude. At the museum, there was a long gold line that separates the world in half and that’s the prime meridian. You can stand on the west side and east side of the world at the same time. It is an awesome feeling!!! 

      In the observatory, I saw different clocks and telescopes. Many of the old clocks were bigger than me. I interviewed Mike Dryland who gives tours. I asked him about the telescopes and clocks. He said, “At night, the stars appears to move. The stars don’t actually move. It’s the earth spinning.  The spinning earth is actually a very good clock.  They used measuring telescopes to measure the position of the stars to get very precise time.”

     The prime meridian helps you know where you are in the world. Dryland says, “The prime meridian was created in 1884. It was done by an argument. It could have been in different places such as Berlin, Naval Observatory in Washington, D.C. or Paris. Greenwich was selected because of the centuries of navigation work done at the observatory.” The next time you see a globe, look for the prime meridian line going through Greenwich, England.