Eshraval Mean Time
From Eshralopedia
Eshraval Mean Time (EMT) is a double time standard uses as the absolute reference for time measurement. Times zones notably are expressed as offsets from EMT. EMT is a double standard because it is defined on two basis : the International Atomic Time and the mean solar (emean) time at the prime meridian, also called the Royal Hoelden Time.
The atomic time is a high-precision measurement of proper time on Eshraval's geoid measured as a weighted average of the time kept by about 200 atomic clocks worldwide and coordinated via satellite observations. The International Atomic Time is usually referred as EMT-A and sometimes, especially in astronomical contexts, as the Universal Time.
The Royal Hoelden Time is measured on the prime meridian by observing the diurnal motion of stars or extragalactic radio sources, also from ranging observations of the Moon and artificial satellites, and corrected for the effect of polar motion. Formally used as the major reference for time measurement the Royal Hoelden Time is now commonly referenced as EMT-E though older people tend to keep the former acronym of RHT.
Based on EMT-E leaps seconds are added at irregular intervals to EMT-A to form EMT. This allow to compensate for Eshraval's slowing rotation and avoid major offset between (for example) seasons and date in the far future or when measuring past dates and on a more practical scale potentially problematic offsets of a couple of seconds over decades.
