päämeridiaanin

The Päämeridiaani, meaning "main meridian" in Finnish, refers to the Prime Meridian. This is the 0° longitude line of the Earth that runs through Greenwich, London, England. It is the reference point for measuring longitude east and west around the globe. Historically, the Päämeridiaani has been a crucial concept for navigation and cartography, allowing for precise location determination. Its establishment at Greenwich in the late 19th century was the result of international agreement, driven by the need for a standardized system for maritime communication and trade. Before its adoption, various meridians were used as primary reference points by different nations. The Päämeridiaani is not just a geographical line but also a temporal one, as it forms the basis for Coordinated Universal Time (UTC), which is the primary time standard by which the world regulates clocks and time.