Where is all time measured from?

Answer 1

The official time all around the world is measured according to cesium atoms.

It turns out that the unchanging transition period of a cesium atom is exactly equivalent to one second. Unlike solar or lunar-based measurements, cesium seconds don't change with latitude or altitude. Since 1997, cesium has been the standard for measuring time.

Answer:

As to where time is measured from, the Prime Meridian, which runs through Greenwich, England, is used as the starting point for the time zones that are used in determining time around the world. All time zones are designated as being either plus or minus from GMT (Greenwich Mean Time), also known as UTC (Coordinated Universal Time). These time zones continue east and west until reaching the International Date Line which runs (more or less) along the 180th meridian.

Several organisations, but most notably the U.S. Naval Observatory, maintain atomic clocks. A "cesium(-beam) atomic clock" (or "cesium-beam frequency standard") is a device that uses as a reference the exact frequency of the microwave spectral line emitted by atoms of the metallic element cesium, in particular its isotope of atomic weight 133. 1 second = 9,192, 631,770 cycles of the standard Cs-133 transition. The USNO master clocks are in Washington, D.C. The alternate master clocks are near Colorado Springs, CO.

Answer 2

Time is MEASURED in different places around the world. For example, the official time for the United States is established by the Naval Observatory. The Royal Observatory in Greenwich England is another institution which measures time. There are other institutions which do this also.

Now, the world is divided in to 24 time zones around the world. That is because the planet is spinning on its axis as it circles the sun. Basically one half of the planet is dark while the other half is in sunlight. Using time zones permits the local residents in a time zone to divide their day into hours of day or night that recur at the same time each day.

Answer 3

From the Prime Meridian of the world in Greenwich England. From there it is measured in 15 degree longitude intervals east and west.

Answer 4

Time is measured in different places around the world

Answer 5

from the Prime Meridian in Greenwich, England