Space Exploration - 360° Panoramic Space

Author: None
Publisher:
Publish Date: 2006-09-01
Features: Greenwich Observatory
To create accurate charts of the positions of the moon and stars, meet the needs of astronomical research, and help navigators determine their location at sea, the British established the world-famous Greenwich Observatory in southeast London in 1675. It is also the oldest observatory still in use. For nearly a century, the time of all countries in the world has been based on Greenwich Mean Time (GMT), which is then converted into the world time. The meridian passing through the Greenwich Observatory was designated as the zero-degree meridian, or the Prime Meridian. The Prime Meridian, also known as the "First Meridian" or "Zero Meridian," is the reference meridian for calculating longitudes on Earth. In the mid-19th century, each country had its own time standard. For example, France used the time standard of the Paris Observatory to determine its time, Russia used the time standard of the Pulkovo Observatory (near Leningrad today), and the United States used the time standard of Washington. Due to the differences in time standards among countries, many difficulties arose in international activities. To eliminate the confusion caused by time differences, the International Meridian Conference decided in 1884 to designate the meridian passing through the transit instrument at the Greenwich Observatory as the Prime Meridian, serving as the global reference for longitudes. Additionally, the mean solar time measured based on the Prime Meridian was established as Greenwich Mean Time (GMT). GMT is the standard time of the United Kingdom and also the basis for timekeeping in other time zones around the world. On December 28, 1999, a new time system—the Greenwich Electronic Time (GET)—was officially introduced, providing a time standard for global e-commerce. The original Greenwich Mean Time (GMT) would still be retained as the world standard time for the 21st century.
During World War II, due to bombing by German aircraft, the Greenwich Observatory suffered severe damage, forcing the relocation of the observatory. In 1953, it was officially moved to Herstmonceux Castle, 70 kilometers southeast of London. The Prime Meridian remains based on the meridian passing through the former site of the Greenwich Observatory.
Although the Greenwich Observatory has now developed into a comprehensive optical observatory in the United Kingdom, due to its heavy burden, it could no longer maintain the "Greenwich Time." Therefore, the British government decided to discontinue the operation of six costly atomic clocks within the observatory starting in 1986.